Appendices

doi:10.55418/9781933477091-appendix01

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Atlases of Tumor and Non-Tumor Pathology, Series 5

Atlas of Placental Pathology

American Registry of Pathology

Volume

DOI:

https://doi.org/10.55418/9781933477091

ISBN-10:

1-933477-09-1

ISBN print:

978-1-933477-09-1

Publication date:

2021

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APPENDIX A: PLACENTAL WEIGHT STANDARDS

Appendix A-1

SINGLETON PLACENTAL WEIGHT (UNFIXED AND TRIMMED) STANDARDS BETWEEN 23 AND 27 WEEKS^a,b

Gestational Age (Weeks)	Percentile (Weight in Grams)
Gestational Age (Weeks)	10th	25th	50th	75th	90th
23	120	152	181	220	260
24	129	153	197	228	280
25	142	169	200	242	270
26	160	184	212	260	300
27	154	186	225	280	330

Gestational Age (Weeks)	Percentile (Weight in Grams)
Gestational Age (Weeks)	10th	25th	50th	75th	90th
23	120	152	181	220	260
24	129	153	197	228	280
25	142	169	200	242	270
26	160	184	212	260	300
27	154	186	225	280	330

Generated from a diverse population from the Midwestern and Eastern United States.

Data from reference 1.

Appendix A-2

SINGLETON PLACENTA WEIGHT (UNFIXED AND TRIMMED) STANDARDS^a,b

Gestational Age (Weeks)	Percentile (Weight in Grams)
Gestational Age (Weeks)	3rd	5th	10th	25th	50th	75th	90th	95th	97th
22		99	107	130	166	206	285	499
23			127	168	188	208	262
24			128	157	192	222	252
25		105	128	153	184	216	299	400
26		107	138	179	200	259	281	570
27		119	130	166	242	310	332	381
28	103	128	140	173	214	261	321	361	371
29	124	135	161	214	252	309	352	496	629
30	185	190	208	269	316	374	433	502	570
31	142	152	175	246	313	360	417	479	579
32	161	214	241	275	318	377	436	461	465
33	190	224	252	286	352	413	446	475	504
34	221	260	283	322	382	430	479	527	558
35	232	250	291	344	401	471	544	600	626
36	270	291	320	369	440	508	580	628	679
37	303	324	349	390	452	531	607	660	692
38	320	335	365	420	484	560	629	675	706
39	330	350	379	426	490	564	635	683	713
40	340	360	390	440	501	572	643	685	715
41	358	379	403	452	515	583	655	705	738
42	370	388	412	460	525	592	658	700	771

Gestational Age (Weeks)	Percentile (Weight in Grams)
Gestational Age (Weeks)	3rd	5th	10th	25th	50th	75th	90th	95th	97th
22		99	107	130	166	206	285	499
23			127	168	188	208	262
24			128	157	192	222	252
25		105	128	153	184	216	299	400
26		107	138	179	200	259	281	570
27		119	130	166	242	310	332	381
28	103	128	140	173	214	261	321	361	371
29	124	135	161	214	252	309	352	496	629
30	185	190	208	269	316	374	433	502	570
31	142	152	175	246	313	360	417	479	579
32	161	214	241	275	318	377	436	461	465
33	190	224	252	286	352	413	446	475	504
34	221	260	283	322	382	430	479	527	558
35	232	250	291	344	401	471	544	600	626
36	270	291	320	369	440	508	580	628	679
37	303	324	349	390	452	531	607	660	692
38	320	335	365	420	484	560	629	675	706
39	330	350	379	426	490	564	635	683	713
40	340	360	390	440	501	572	643	685	715
41	358	379	403	452	515	583	655	705	738
42	370	388	412	460	525	592	658	700	771

Generated from a diverse group of patients in Massachusetts between 1995 and 1997.

Data from reference 2.

Appendix A-3

PLACENTAL WEIGHT (UNFIXED AND UNTRIMMED) STANDARDS FOR TERM PLACENTAS BY MODE OF DELIVERY^a,b,c

Gestational Age (Weeks)	Vaginal Delivery			Caesarean Delivery
Gestational Age (Weeks)	5th	50th	95th	5th	50th	95th
37 + 0 to 37 + 6	360 (358-362)	501 (499-503)	697 (695-699)	396 (394-398)	579 (577-581)	846 (844-848)
38 + 0 to 38 + 6	374 (372-376)	516 (514-518)	712 (710-714)	411 (409-413)	593 (591-595)	858 (856-860)
39 + 0 to 39 + 6	388 (386-390)	531 (529-533)	726 (724-728)	427 (425-429)	609 (607-611)	870 (868-872)
40 + 0 to 40 + 6	401 (399-403)	545 (543-547)	740 (738-742)	443 (441-445)	625 (623-627)	882
41 + 0 to 41 + 6	415 (413-417)	560 (558-562)	756 (754-758)	461 (459-463)	642 (640-644)	894 (892-896)

Gestational Age (Weeks)	Vaginal Delivery			Caesarean Delivery
Gestational Age (Weeks)	5th	50th	95th	5th	50th	95th
37 + 0 to 37 + 6	360 (358-362)	501 (499-503)	697 (695-699)	396 (394-398)	579 (577-581)	846 (844-848)
38 + 0 to 38 + 6	374 (372-376)	516 (514-518)	712 (710-714)	411 (409-413)	593 (591-595)	858 (856-860)
39 + 0 to 39 + 6	388 (386-390)	531 (529-533)	726 (724-728)	427 (425-429)	609 (607-611)	870 (868-872)
40 + 0 to 40 + 6	401 (399-403)	545 (543-547)	740 (738-742)	443 (441-445)	625 (623-627)	882
41 + 0 to 41 + 6	415 (413-417)	560 (558-562)	756 (754-758)	461 (459-463)	642 (640-644)	894 (892-896)

Generated from healthy Swiss population between 1995 and 2002.

Data from reference 3.

Percentile weights in grams.

Appendix A-4

SINGLETON PLACENTA UNFIXED AND TRIMMED WEIGHT STANDARDS FOR NORTH AMERICA (CANADIAN POPULATION) GENERATED BETWEEN 2001 AND 2007 (BY GENDER)^a

Gestational Age (Weeks)	Percentile (Weight in Grams) Female/Male
	3rd		10th		25th		50th		75th		90th		97th
	F	M	F	M	F	M	F	M	F	M	F	M	F	M
24	134.1	164.7	161.7	199.6	195.7	242.7	242.3	301.7	300.7	375.1	365.9	456.6	444.7	554.5
25	153.0	176.8	183.6	213.3	221.2	258.1	272.6	319.1	336.6	394.7	407.5	478.1	493.0	577.8
26	171.8	188.9	205.3	226.9	246.2	273.3	301.8	336.1	370.7	413.5	446.7	498.5	537.9	599.7
27	190.1	201.6	226.2	241.0	270.1	288.8	329.4	353.3	402.5	432.4	482.7	518.7	578.4	621.0
28	208.4	215.0	246.8	255.9	293.4	305.2	356.1	371.4	432.8	452.1	516.6	539.8	616.1	643.2
29	227.5	230.4	268.3	272.8	317.5	323.9	383.3	392.0	463.5	474.7	550.7	564.0	653.6	668.9
30	248.3	248.7	291.6	293.1	343.4	346.3	412.5	417.0	496.3	502.2	586.8	593.9	693.3	700.9
31	271.3	270.0	317.1	316.8	371.9	372.6	444.4	446.2	531.9	534.6	626.0	629.1	736.0	739.0
32	295.9	293.4	344.4	342.6	402.0	401.0	478.0	477.7	569.0	569.3	666.5	666.8	780.0	779.5
33	321.2	318.1	372.2	369.7	432.5	430.6	511.6	510.3	606.0	604.9	706.4	705.1	822.7	820.4
34	346.6	343.4	399.9	397.3	462.5	460.6	544.3	543.0	641.4	640.2	744.2	742.7	862.6	860.1
35	370.7	368.3	425.7	424.1	490.2	489.4	573.9	573.9	672.7	673.1	776.8	777.1	896.1	895.7
36	393.0	392.1	449.3	449.4	515.0	516.2	599.9	602.1	699.5	702.5	803.9	807.3	923.1	926.1
37	413.3	414.8	470.4	473.3	536.7	541.0	622.0	627.8	721.4	728.7	825.2	833.4	943.0	951.7
38	431.8	434.9	489.3	493.9	555.7	562.0	640.7	648.8	739.3	749.2	841.7	852.9	957.2	969.4
39	447.7	452.1	505.0	511.2	571.0	578.9	654.9	664.9	751.8	763.8	851.8	865.5	964.1	979.3
40	463.2	468.9	520.2	527.7	585.4	595.0	668.0	679.9	762.8	777.0	860.2	876.4	969.1	987.1
41	478.8	486.5	535.3	545.2	599.7	611.8	680.8	695.6	773.4	791.0	868.1	888.0	973.4	995.6
42	490.9	501.6	546.4	559.5	609.3	625.1	688.2	707.1	777.8	799.9	868.8	894.0	969.6	997.8
43	499.6	515.0	553.7	571.9	614.6	636.0	690.6	715.8	776.5	805.7	863.4	896.3	959.1	995.9
44	507.1	528.5	559.5	584.3	618.2	646.9	691.2	724.3	773.1	811.2	855.5	898.3	945.9	993.6

Gestational Age (Weeks)	Percentile (Weight in Grams) Female/Male
	3rd		10th		25th		50th		75th		90th		97th
	F	M	F	M	F	M	F	M	F	M	F	M	F	M
24	134.1	164.7	161.7	199.6	195.7	242.7	242.3	301.7	300.7	375.1	365.9	456.6	444.7	554.5
25	153.0	176.8	183.6	213.3	221.2	258.1	272.6	319.1	336.6	394.7	407.5	478.1	493.0	577.8
26	171.8	188.9	205.3	226.9	246.2	273.3	301.8	336.1	370.7	413.5	446.7	498.5	537.9	599.7
27	190.1	201.6	226.2	241.0	270.1	288.8	329.4	353.3	402.5	432.4	482.7	518.7	578.4	621.0
28	208.4	215.0	246.8	255.9	293.4	305.2	356.1	371.4	432.8	452.1	516.6	539.8	616.1	643.2
29	227.5	230.4	268.3	272.8	317.5	323.9	383.3	392.0	463.5	474.7	550.7	564.0	653.6	668.9
30	248.3	248.7	291.6	293.1	343.4	346.3	412.5	417.0	496.3	502.2	586.8	593.9	693.3	700.9
31	271.3	270.0	317.1	316.8	371.9	372.6	444.4	446.2	531.9	534.6	626.0	629.1	736.0	739.0
32	295.9	293.4	344.4	342.6	402.0	401.0	478.0	477.7	569.0	569.3	666.5	666.8	780.0	779.5
33	321.2	318.1	372.2	369.7	432.5	430.6	511.6	510.3	606.0	604.9	706.4	705.1	822.7	820.4
34	346.6	343.4	399.9	397.3	462.5	460.6	544.3	543.0	641.4	640.2	744.2	742.7	862.6	860.1
35	370.7	368.3	425.7	424.1	490.2	489.4	573.9	573.9	672.7	673.1	776.8	777.1	896.1	895.7
36	393.0	392.1	449.3	449.4	515.0	516.2	599.9	602.1	699.5	702.5	803.9	807.3	923.1	926.1
37	413.3	414.8	470.4	473.3	536.7	541.0	622.0	627.8	721.4	728.7	825.2	833.4	943.0	951.7
38	431.8	434.9	489.3	493.9	555.7	562.0	640.7	648.8	739.3	749.2	841.7	852.9	957.2	969.4
39	447.7	452.1	505.0	511.2	571.0	578.9	654.9	664.9	751.8	763.8	851.8	865.5	964.1	979.3
40	463.2	468.9	520.2	527.7	585.4	595.0	668.0	679.9	762.8	777.0	860.2	876.4	969.1	987.1
41	478.8	486.5	535.3	545.2	599.7	611.8	680.8	695.6	773.4	791.0	868.1	888.0	973.4	995.6
42	490.9	501.6	546.4	559.5	609.3	625.1	688.2	707.1	777.8	799.9	868.8	894.0	969.6	997.8
43	499.6	515.0	553.7	571.9	614.6	636.0	690.6	715.8	776.5	805.7	863.4	896.3	959.1	995.9
44	507.1	528.5	559.5	584.3	618.2	646.9	691.2	724.3	773.1	811.2	855.5	898.3	945.9	993.6

Data from reference 4.

Appendix A-5

PLACENTAL WEIGHT PERCENTILES FOR THE NORWEGIAN POPULATION GENERATED BETWEEN 1999 AND 2002^a,b

Gestational Age (Weeks)	Percentile (Weight In Grams) Female/Male
	3rd		10th		50th		90th		97th
	F	M	F	M	F	M	F	M	F	M
24	130	150	160	180	240	260	350	380	400	460
25	130	150	170	180	260	270	370	400	430	470
26	140	150	180	190	270	290	400	420	460	490
27	150	160	190	200	300	310	430	450	490	520
28	170	170	210	220	320	340	460	480	530	550
29	190	190	230	240	350	360	500	510	570	590
30	210	210	260	270	390	400	540	550	610	630
31	240	240	290	290	420	430	570	590	660	670
32	260	260	320	320	450	460	610	620	700	710
33	290	290	350	350	490	500	650	660	740	750
34	320	320	380	380	520	530	690	700	780	790
35	350	350	410	410	560	560	730	740	820	830
36	370	370	440	440	590	590	760	770	860	870
37	400	400	460	460	610	620	800	810	890	900
38	420	420	480	490	640	650	820	840	920	930
39	440	440	500	510	660	670	840	860	950	960
40	460	460	520	530	670	690	860	880	960	980
41	470	470	530	540	680	700	870	890	970	990
42	470	480	530	540	690	700	870	900	980	1000
43	470	480	530	540	680	700	870	890	980	1000
44	460	470	520	540	670	690	860	880	960	980

Gestational Age (Weeks)	Percentile (Weight In Grams) Female/Male
	3rd		10th		50th		90th		97th
	F	M	F	M	F	M	F	M	F	M
24	130	150	160	180	240	260	350	380	400	460
25	130	150	170	180	260	270	370	400	430	470
26	140	150	180	190	270	290	400	420	460	490
27	150	160	190	200	300	310	430	450	490	520
28	170	170	210	220	320	340	460	480	530	550
29	190	190	230	240	350	360	500	510	570	590
30	210	210	260	270	390	400	540	550	610	630
31	240	240	290	290	420	430	570	590	660	670
32	260	260	320	320	450	460	610	620	700	710
33	290	290	350	350	490	500	650	660	740	750
34	320	320	380	380	520	530	690	700	780	790
35	350	350	410	410	560	560	730	740	820	830
36	370	370	440	440	590	590	760	770	860	870
37	400	400	460	460	610	620	800	810	890	900
38	420	420	480	490	640	650	820	840	920	930
39	440	440	500	510	660	670	840	860	950	960
40	460	460	520	530	670	690	860	880	960	980
41	470	470	530	540	680	700	870	890	970	990
42	470	480	530	540	690	700	870	900	980	1000
43	470	480	530	540	680	700	870	890	980	1000
44	460	470	520	540	670	690	860	880	960	980

Data from reference 5.

Data is presumed to have been generated in the unfixed and trimmed state.

Appendix A-6

PLACENTAL WEIGHT (UNFIXED AND UNTRIMMED) STANDARDS FOR FEMALE BIRTHS IN THE JAPANESE POPULATION^a,b

Gestational Age (Weeks)	Percentile
	10th		50th		90th
	P^c	M	P	M	P	M
22	128	139	205	217	323	347
23	145	156	231	242	358	380
24	163	173	257	267	392	412
25	180	191	282	292	426	443
26	198	209	308	317	458	475
27	217	227	334	343	489	505
28	236	246	359	368	519	534
29	255	265	383	392	548	562
30	274	284	408	415	574	587
31	293	303	431	438	599	611
32	313	322	452	459	621	633
33	332	341	473	479	641	652
34	350	359	491	498	657	670
35	367	377	506	515	669	684
36	384	394	520	530	679	696
37	399	410	532	544	686	706
38	414	424	543	555	693	713
39	428	438	554	567	701	721
40	443	453	567	581	712	733
41	457	469	581	597	726	747

Gestational Age (Weeks)	Percentile
	10th		50th		90th
	P^c	M	P	M	P	M
22	128	139	205	217	323	347
23	145	156	231	242	358	380
24	163	173	257	267	392	412
25	180	191	282	292	426	443
26	198	209	308	317	458	475
27	217	227	334	343	489	505
28	236	246	359	368	519	534
29	255	265	383	392	548	562
30	274	284	408	415	574	587
31	293	303	431	438	599	611
32	313	322	452	459	621	633
33	332	341	473	479	641	652
34	350	359	491	498	657	670
35	367	377	506	515	669	684
36	384	394	520	530	679	696
37	399	410	532	544	686	706
38	414	424	543	555	693	713
39	428	438	554	567	701	721
40	443	453	567	581	712	733
41	457	469	581	597	726	747

Between 2001-2002; according to maternal parity.

Data from reference 6.

P = primiparity; M = multiparity.

Appendix A-7

PLACENTAL WEIGHT (UNFIXED AND UNTRIMMED) STANDARDS FOR MALE BIRTHS IN THE JAPANESE POPULATION^a,b

Gestational Age (Weeks)	Percentile
	10th		50th		90th
	P^c	M	P	M	P	M
22	127	158	210	234	329	350
23	142	175	233	257	359	379
24	157	191	256	281	388	409
25	173	208	279	304	417	438
26	190	224	303	327	445	466
27	208	241	327	350	475	493
28	227	259	352	373	504	520
29	247	276	377	397	534	547
30	268	294	402	420	563	573
31	289	313	426	443	590	599
32	310	332	449	465	614	624
33	330	350	469	486	634	647
34	349	368	488	505	652	667
35	367	385	505	522	666	684
36	384	401	520	537	679	698
37	401	416	534	551	690	710
38	418	431	548	565	700	721
39	434	447	563	579	712	733
40	450	464	557	596	724	748
41	465	482	591	613	736	763

Gestational Age (Weeks)	Percentile
	10th		50th		90th
	P^c	M	P	M	P	M
22	127	158	210	234	329	350
23	142	175	233	257	359	379
24	157	191	256	281	388	409
25	173	208	279	304	417	438
26	190	224	303	327	445	466
27	208	241	327	350	475	493
28	227	259	352	373	504	520
29	247	276	377	397	534	547
30	268	294	402	420	563	573
31	289	313	426	443	590	599
32	310	332	449	465	614	624
33	330	350	469	486	634	647
34	349	368	488	505	652	667
35	367	385	505	522	666	684
36	384	401	520	537	679	698
37	401	416	534	551	690	710
38	418	431	548	565	700	721
39	434	447	563	579	712	733
40	450	464	557	596	724	748
41	465	482	591	613	736	763

Between 2001 and 2002 according to maternal parity.

Data from reference 6.

P = primiparity; M = multiparity.

Appendix A-8

DICHORIONIC-DIAMNIOTIC TWIN PLACENTAL WEIGHT (UNFIXED AND TRIMMED) STANDARDS^a,b

Gestational Age (Weeks)	Percentile (Weight in Grams)
Gestational Age (Weeks)	3rd	10th	25th	50th	75th	90th	97th
24	160.2	243.5	327.0	419.2	510.7	592.8	673.5
25	186.7	276.5	366.6	465.9	564.8	653.3	740.4
26	218.2	315.3	412.8	520.4	627.4	723.3	817.6
27	257.1	363.1	469.7	587.2	704.2	809.0	912.1
28	304.2	420.5	537.4	666.6	795.0	910.1	1023.4
29	358.0	485.1	612.8	753.9	894.3	1020.2	1144.0
30	412.5	548.3	685.0	836.0	986.2	1120.9	1253.4
31	462.2	603.5	745.7	902.8	1059.1	1199.3	1337.3
32	507.3	651.0	795.8	955.8	1115.1	1258.0	1398.6
33	551.4	696.3	842.3	1003.7	1164.3	1308.4	1450.2
34	596.2	741.3	887.5	1049.2	1210.1	1354.5	1496.7
35	638.2	781.8	926.6	1086.7	1246.2	1389.3	1530.2
36	679.7	820.9	963.4	1121.0	1277.9	1418.8	1557.5
37	725.6	864.7	1004.9	1160.2	1314.8	1453.6	1590.3
38	772.3	908.6	1046.1	1198.4	1350.1	1486.2	1620.3
39	805.2	935.9	1067.8	1213.8	1359.4	1490.0	1618.6
40	830.1	953.8	1078.6	1216.9	1354.7	1478.4	1600.3
41	855.7	972.4	1090.2	1220.8	1350.9	1467.8	1582.9
42	884.3	994.4	1105.6	1228.8	1351.6	1461.9	1570.6

Gestational Age (Weeks)	Percentile (Weight in Grams)
Gestational Age (Weeks)	3rd	10th	25th	50th	75th	90th	97th
24	160.2	243.5	327.0	419.2	510.7	592.8	673.5
25	186.7	276.5	366.6	465.9	564.8	653.3	740.4
26	218.2	315.3	412.8	520.4	627.4	723.3	817.6
27	257.1	363.1	469.7	587.2	704.2	809.0	912.1
28	304.2	420.5	537.4	666.6	795.0	910.1	1023.4
29	358.0	485.1	612.8	753.9	894.3	1020.2	1144.0
30	412.5	548.3	685.0	836.0	986.2	1120.9	1253.4
31	462.2	603.5	745.7	902.8	1059.1	1199.3	1337.3
32	507.3	651.0	795.8	955.8	1115.1	1258.0	1398.6
33	551.4	696.3	842.3	1003.7	1164.3	1308.4	1450.2
34	596.2	741.3	887.5	1049.2	1210.1	1354.5	1496.7
35	638.2	781.8	926.6	1086.7	1246.2	1389.3	1530.2
36	679.7	820.9	963.4	1121.0	1277.9	1418.8	1557.5
37	725.6	864.7	1004.9	1160.2	1314.8	1453.6	1590.3
38	772.3	908.6	1046.1	1198.4	1350.1	1486.2	1620.3
39	805.2	935.9	1067.8	1213.8	1359.4	1490.0	1618.6
40	830.1	953.8	1078.6	1216.9	1354.7	1478.4	1600.3
41	855.7	972.4	1090.2	1220.8	1350.9	1467.8	1582.9
42	884.3	994.4	1105.6	1228.8	1351.6	1461.9	1570.6

Generated from a Canadian population in the early 2000s.

Data from reference 4.

Appendix A-9

TRIPLET PLACENTA WEIGHT (UNFIXED AND TRIMMED) STANDARDS (WEIGHT IN GRAMS)^a,b

Gestational Age (Weeks)	10th Percentile	Mean	90th Percentile
20	226	253	285
21	257	284	320
22	289	319	345
23	331	361	400
24	371	406	445
25	408	456	498
26	444	509	558
27	480	564	630
28	516	621	697
29	553	679	772
30	591	738	849
31	631	797	925
32	674	855	1000
33	719	911	1072
34	768	965	1139
35	821	1017	1200
36	878	1065	1253
37	940	1108	1297
38	1007	1147	1330

Gestational Age (Weeks)	10th Percentile	Mean	90th Percentile
20	226	253	285
21	257	284	320
22	289	319	345
23	331	361	400
24	371	406	445
25	408	456	498
26	444	509	558
27	480	564	630
28	516	621	697
29	553	679	772
30	591	738	849
31	631	797	925
32	674	855	1000
33	719	911	1072
34	768	965	1139
35	821	1017	1200
36	878	1065	1253
37	940	1108	1297
38	1007	1147	1330

Generated from a northeastern United States population.

Data from reference 7.

Appendix A-10

PERCENTILES OF SINGLETON PLACENTAL WEIGHT (UNFIXED AND TRIMMED) BY BIRTH WEIGHT FOR FEMALE AND MALE INFANTS^a,b

Birth Weight (Grams)	Percentile (Placental Weight In Grams) Female/Male
	3rd		10th		25th		50th		75th		90th		97th
	F	M	F	M	F	M	F	M	F	M	F	M	F	M
500	153.3	154.1	187.5	228.9	222.2	304.7	260.7	388.8	299.2	473.0	333.9	548.8	368.1	623.6
750	189.2	173.3	229.6	245.9	270.5	319.4	316.0	401.1	361.4	482.8	402.3	556.4	442.7	628.9
1000	225.7	191.2	271.8	260.5	318.5	330.8	370.4	408.8	422.2	486.8	468.9	557.1	515.0	626.4
1250	260.0	210.1	310.7	276.4	362.1	343.5	419.2	418.0	476.3	492.6	527.6	559.7	578.4	625.9
1500	288.7	232.7	342.5	296.8	397.0	361.7	457.5	433.8	518.0	506.0	572.5	570.9	626.3	635.0
1750	311.3	260.2	366.5	323.3	422.5	387.1	484.8	458.1	547.0	529.1	603.0	592.9	658.3	656.0
2000	330.4	291.7	386.3	354.3	443.0	417.8	505.9	488.3	568.9	558.8	625.5	622.3	681.5	684.9
2250	349.8	324.3	406.3	386.6	463.4	449.7	527.0	519.8	590.5	589.9	647.7	653.0	704.2	715.3
2500	371.9	355.7	429.2	417.4	487.3	479.9	551.8	549.4	616.3	618.9	674.4	681.4	731.7	743.1
2750	398.4	387.0	457.2	448.4	516.8	510.5	583.1	579.6	649.3	648.7	709.0	710.9	767.8	772.2
3000	430.9	421.8	492.4	483.8	554.6	546.7	623.7	616.5	692.8	686.3	755.0	749.1	816.6	811.1
3250	466.3	475.0	530.8	520.4	596.2	584.7	668.8	656.1	741.4	727.4	806.8	791.7	871.3	855.1
3500	502.4	493.2	570.2	559.1	638.8	625.8	715.1	700.0	791.4	774.1	860.1	840.8	927.8	906.7
3750	539.7	531.2	610.8	600.5	682.9	670.7	762.9	748.7	843.0	826.7	915.0	896.9	986.1	966.2
4000	579.4	571.7	653.9	645.1	729.5	719.5	813.5	802.1	897.4	884.7	973.0	959.0	1047.5	1032.4
4250	620.8	615.0	698.8	692.8	777.9	771.7	865.7	859.3	953.5	947.0	1032.6	1025.8	1110.6	1103.7
4500	667.3	656.5	749.2	738.5	832.2	821.5	924.4	913.8	1016.5	1006.1	1099.5	1089.1	1181.4	1171.1
4750	716.5	695.1	802.4	780.7	889.4	867.4	986.1	963.7	1082.8	1060.1	1169.8	1146.8	1255.7	1232.4
5000	766.9	733.3	856.7	822.3	947.7	912.4	1048.8	1012.6	1149.9	1112.7	1240.9	1202.9	1330.8	1291.9
5250	818.1	773.4	911.7	865.8	1006.5	959.5	1111.9	1063.5	1217.3	1167.6	1312.1	1261.3	1405.7	1353.7
5500	869.7	814.5	966.9	910.4	1006.4	1007.6	1174.8	1115.6	1284.3	1223.5	1382.7	1320.7	1479.9	1416.7

Birth Weight (Grams)	Percentile (Placental Weight In Grams) Female/Male
	3rd		10th		25th		50th		75th		90th		97th
	F	M	F	M	F	M	F	M	F	M	F	M	F	M
500	153.3	154.1	187.5	228.9	222.2	304.7	260.7	388.8	299.2	473.0	333.9	548.8	368.1	623.6
750	189.2	173.3	229.6	245.9	270.5	319.4	316.0	401.1	361.4	482.8	402.3	556.4	442.7	628.9
1000	225.7	191.2	271.8	260.5	318.5	330.8	370.4	408.8	422.2	486.8	468.9	557.1	515.0	626.4
1250	260.0	210.1	310.7	276.4	362.1	343.5	419.2	418.0	476.3	492.6	527.6	559.7	578.4	625.9
1500	288.7	232.7	342.5	296.8	397.0	361.7	457.5	433.8	518.0	506.0	572.5	570.9	626.3	635.0
1750	311.3	260.2	366.5	323.3	422.5	387.1	484.8	458.1	547.0	529.1	603.0	592.9	658.3	656.0
2000	330.4	291.7	386.3	354.3	443.0	417.8	505.9	488.3	568.9	558.8	625.5	622.3	681.5	684.9
2250	349.8	324.3	406.3	386.6	463.4	449.7	527.0	519.8	590.5	589.9	647.7	653.0	704.2	715.3
2500	371.9	355.7	429.2	417.4	487.3	479.9	551.8	549.4	616.3	618.9	674.4	681.4	731.7	743.1
2750	398.4	387.0	457.2	448.4	516.8	510.5	583.1	579.6	649.3	648.7	709.0	710.9	767.8	772.2
3000	430.9	421.8	492.4	483.8	554.6	546.7	623.7	616.5	692.8	686.3	755.0	749.1	816.6	811.1
3250	466.3	475.0	530.8	520.4	596.2	584.7	668.8	656.1	741.4	727.4	806.8	791.7	871.3	855.1
3500	502.4	493.2	570.2	559.1	638.8	625.8	715.1	700.0	791.4	774.1	860.1	840.8	927.8	906.7
3750	539.7	531.2	610.8	600.5	682.9	670.7	762.9	748.7	843.0	826.7	915.0	896.9	986.1	966.2
4000	579.4	571.7	653.9	645.1	729.5	719.5	813.5	802.1	897.4	884.7	973.0	959.0	1047.5	1032.4
4250	620.8	615.0	698.8	692.8	777.9	771.7	865.7	859.3	953.5	947.0	1032.6	1025.8	1110.6	1103.7
4500	667.3	656.5	749.2	738.5	832.2	821.5	924.4	913.8	1016.5	1006.1	1099.5	1089.1	1181.4	1171.1
4750	716.5	695.1	802.4	780.7	889.4	867.4	986.1	963.7	1082.8	1060.1	1169.8	1146.8	1255.7	1232.4
5000	766.9	733.3	856.7	822.3	947.7	912.4	1048.8	1012.6	1149.9	1112.7	1240.9	1202.9	1330.8	1291.9
5250	818.1	773.4	911.7	865.8	1006.5	959.5	1111.9	1063.5	1217.3	1167.6	1312.1	1261.3	1405.7	1353.7
5500	869.7	814.5	966.9	910.4	1006.4	1007.6	1174.8	1115.6	1284.3	1223.5	1382.7	1320.7	1479.9	1416.7

Generated from a Canadian population between 2001 and 2007.

Data from reference 4.

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Hecht

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APPENDIX B: UMBILICAL CORD LENGTH STANDARDS

Appendix B-1

SINGLETON UMBILICAL CORD LENGTH (CM) BY GESTATIONAL AGE AND INFANT GENDER^a,b,c

Gestational Age (Weeks)	Percentile (Length in cm) Female/Male
	3rd		10th		25th		50th		75th		90th		97th
	F	M	F	M	F	M	F	M	F	M	F	M	F	M
34	29	33	37	38	44	46	52	54	60	63	70	73	83	86
36	32	35	39	41	46	49	53	56	62	65	71	74	83	87
37	34	36	40	42	47	49	54	57	63	67	72	75	82	87
38	35.5	36	41	42	47	49	55	58	64	68	73	76	84	87
39	36	37	41.5	43	48	50	56	59	65	69	74	77	85	88
40	36	38	42	44.5	49	52	57	60	66	70	76	79	85	90
41	37	39	43.5	46	50	53	58	62	67	71	76	81	87	91
42	37	39	44	46	51	53	59	62	68	71	77	81	89	91
43	37	38	44	45	51	52	59	61	68	71	78	80	89	91

Gestational Age (Weeks)	Percentile (Length in cm) Female/Male
	3rd		10th		25th		50th		75th		90th		97th
	F	M	F	M	F	M	F	M	F	M	F	M	F	M
34	29	33	37	38	44	46	52	54	60	63	70	73	83	86
36	32	35	39	41	46	49	53	56	62	65	71	74	83	87
37	34	36	40	42	47	49	54	57	63	67	72	75	82	87
38	35.5	36	41	42	47	49	55	58	64	68	73	76	84	87
39	36	37	41.5	43	48	50	56	59	65	69	74	77	85	88
40	36	38	42	44.5	49	52	57	60	66	70	76	79	85	90
41	37	39	43.5	46	50	53	58	62	67	71	76	81	87	91
42	37	39	44	46	51	53	59	62	68	71	77	81	89	91
43	37	38	44	45	51	52	59	61	68	71	78	80	89	91

Generated from a white population from the United States prior to 1966.

Data from reference 1.

These values are approximated from the percentile curve charts presented in the referenced publication.

Appendix B-2

PERCENTILE CHARTS FOR UMBILICAL CORD LENGTH GENERATED FROM A FINNISH POPULATION BETWEEN 1989 AND 2011^a

UMBILICAL CORD LENGTH PERCENTILES: FEMALE
Gestational Age (Weeks)	Percentile (Length in cm)
Gestational Age (Weeks)	10th	50th	90th
22	22.9	33.3	48.7
23	23.7	34.3	49.7
24	24.6	35.3	50.7
25	25.4	36.3	51.7
26	26.2	37.3	52.6
27	27.0	38.3	53.6
28	27.8	39.4	54.8
29	28.8	40.6	56.2
30	29.8	41.9	57.7
31	30.9	43.4	59.4
32	32.1	44.9	61.2
33	33.4	46.5	63.0
34	34.7	48.1	65.0
35	36.1	49.8	66.9
36	37.7	51.6	68.9
37	39.3	53.3	70.7
38	40.8	54.8	72.2
39	42.3	56.3	73.7
40	43.8	57.7	75.3
41	44.9	58.9	76.8
42	45.7	59.7	77.8
43	46.4	60.5	78.6
44	46.8	60.9	79.1

UMBILICAL CORD LENGTH PERCENTILES: FEMALE
Gestational Age (Weeks)	Percentile (Length in cm)
Gestational Age (Weeks)	10th	50th	90th
22	22.9	33.3	48.7
23	23.7	34.3	49.7
24	24.6	35.3	50.7
25	25.4	36.3	51.7
26	26.2	37.3	52.6
27	27.0	38.3	53.6
28	27.8	39.4	54.8
29	28.8	40.6	56.2
30	29.8	41.9	57.7
31	30.9	43.4	59.4
32	32.1	44.9	61.2
33	33.4	46.5	63.0
34	34.7	48.1	65.0
35	36.1	49.8	66.9
36	37.7	51.6	68.9
37	39.3	53.3	70.7
38	40.8	54.8	72.2
39	42.3	56.3	73.7
40	43.8	57.7	75.3
41	44.9	58.9	76.8
42	45.7	59.7	77.8
43	46.4	60.5	78.6
44	46.8	60.9	79.1

UMBILICAL CORD LENGTH PERCENTILES: MALE
Gestational Age (Weeks)	Percentile (Length in cm)
Gestational Age (Weeks)	10th	50th	90th
22	24.6	34.6	48.6
23	25.3	35.5	50.1
24	25.9	36.5	51.7
25	26.5	37.5	53.2
26	27.3	38.5	54.7
27	28.0	39.6	56.2
28	29.0	40.8	57.7
29	30.0	42.1	59.3
30	31.2	43.5	60.9
31	32.6	45.1	62.6
32	34.1	46.8	64.5
33	35.7	48.6	66.4
34	37.3	50.5	68.4
35	38.9	52.5	70.5
36	40.5	54.3	72.4
37	41.9	55.9	74.1
38	43.1	57.3	75.5
39	44.5	58.8	77.0
40	45.7	60.1	78.5
41	46.4	60.9	79.6
42	46.5	61.2	80.1
43	46.5	61.2	80.5
44	46.4	61.2	80.7

UMBILICAL CORD LENGTH PERCENTILES: MALE
Gestational Age (Weeks)	Percentile (Length in cm)
Gestational Age (Weeks)	10th	50th	90th
22	24.6	34.6	48.6
23	25.3	35.5	50.1
24	25.9	36.5	51.7
25	26.5	37.5	53.2
26	27.3	38.5	54.7
27	28.0	39.6	56.2
28	29.0	40.8	57.7
29	30.0	42.1	59.3
30	31.2	43.5	60.9
31	32.6	45.1	62.6
32	34.1	46.8	64.5
33	35.7	48.6	66.4
34	37.3	50.5	68.4
35	38.9	52.5	70.5
36	40.5	54.3	72.4
37	41.9	55.9	74.1
38	43.1	57.3	75.5
39	44.5	58.8	77.0
40	45.7	60.1	78.5
41	46.4	60.9	79.6
42	46.5	61.2	80.1
43	46.5	61.2	80.5
44	46.4	61.2	80.7

Data from reference 2.

Appendix B References

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APPENDIX C: UMBILICAL CORD DIAMETER STANDARDS

Appendix C-1

UMBILICAL CORD DIAMETER (CM) PERCENTILES BY GESTATIONAL AGE^a,b

Gestational Age (Weeks)	Percentile (Diameter in cm)
Gestational Age (Weeks)	10th	50th	90th
18	0.36	0.46	0.61
19	0.43	0.54	0.68
20	0.50	0.60	0.73
21	0.56	0.67	0.79
22	0.62	0.72	0.84
23	0.67	0.78	0.88
24	0.72	0.83	0.93
25	0.77	0.87	0.97
26	0.80	0.91	1.01
27	0.83	0.94	1.05
28	0.85	0.97	1.09
29	0.87	1.00	1.12
30	0.88	1.02	1.15
31	0.88	1.03	1.18
32	0.88	1.05	1.20
33	0.88	1.05	1.22
34	0.87	1.06	1.23
35	0.86	1.06	1.24
36	0.85	1.05	1.25
37	0.84	1.05	1.24
38	0.83	1.03	1.23
39	0.82	1.02	1.22
40	0.81	1.00	1.19
41	0.80	0.98	1.16

Gestational Age (Weeks)	Percentile (Diameter in cm)
Gestational Age (Weeks)	10th	50th	90th
18	0.36	0.46	0.61
19	0.43	0.54	0.68
20	0.50	0.60	0.73
21	0.56	0.67	0.79
22	0.62	0.72	0.84
23	0.67	0.78	0.88
24	0.72	0.83	0.93
25	0.77	0.87	0.97
26	0.80	0.91	1.01
27	0.83	0.94	1.05
28	0.85	0.97	1.09
29	0.87	1.00	1.12
30	0.88	1.02	1.15
31	0.88	1.03	1.18
32	0.88	1.05	1.20
33	0.88	1.05	1.22
34	0.87	1.06	1.23
35	0.86	1.06	1.24
36	0.85	1.05	1.25
37	0.84	1.05	1.24
38	0.83	1.03	1.23
39	0.82	1.02	1.22
40	0.81	1.00	1.19
41	0.80	0.98	1.16

Data from reference 1.

From a Canadian population in 2005.

Appendix C-2

SINGLETON UMBILICAL CORD CROSS SECTIONAL AREA (MM²) PERCENTILES BY GESTATIONAL AGE^a,b

Gestational Age (Weeks)	Percentiles
Gestational Age (Weeks)	5th	10th	50th	90th	95th
24	78.4	91.1	135.9	180.7	193.4
25	91.7	104.9	151.3	197.8	211.0
26	103.6	117.2	165.3	213.4	227.0
27	114.0	128.1	177.8	227.5	241.6
28	122.9	137.4	188.8	240.2	254.7
29	130.3	145.3	198.4	251.4	266.4
30	136.3	151.8	206.4	261.1	276.6
31	140.8	156.8	213.1	269.4	285.3
32	143.9	160.3	218.2	276.2	292.6
33	145.5	162.4	221.9	281.5	298.4
34	145.6	163.0	224.2	285.4	302.7
35	144.3	162.1	224.9	287.8	305.6
36	141.5	159.8	224.2	288.7	307.0
37	137.2	156.0	222.1	288.2	307.0
38	131.5	150.7	218.5	286.2	305.5
39	124.3	144.0	213.4	282.8	302.5

Gestational Age (Weeks)	Percentiles
Gestational Age (Weeks)	5th	10th	50th	90th	95th
24	78.4	91.1	135.9	180.7	193.4
25	91.7	104.9	151.3	197.8	211.0
26	103.6	117.2	165.3	213.4	227.0
27	114.0	128.1	177.8	227.5	241.6
28	122.9	137.4	188.8	240.2	254.7
29	130.3	145.3	198.4	251.4	266.4
30	136.3	151.8	206.4	261.1	276.6
31	140.8	156.8	213.1	269.4	285.3
32	143.9	160.3	218.2	276.2	292.6
33	145.5	162.4	221.9	281.5	298.4
34	145.6	163.0	224.2	285.4	302.7
35	144.3	162.1	224.9	287.8	305.6
36	141.5	159.8	224.2	288.7	307.0
37	137.2	156.0	222.1	288.2	307.0
38	131.5	150.7	218.5	286.2	305.5
39	124.3	144.0	213.4	282.8	302.5

Generated from a Brazilian population prior to 2006.

Data from reference 2.

Appendix C-3

SINGLETON UMBILICAL CORD DIAMETER (MM) AND CROSS SECTIONAL UMBILICAL CORD AREA (MM²) PERCENTILES BY GESTATIONAL AGE^a,b

Gestational Age (Weeks)	Diameter (Mean)	Area (Mean)	Area-Percentiles
Gestational Age (Weeks)	Diameter (Mean)	Area (Mean)	10th	50th	90th
12	4.5	16.5	9.89	15.03	22.84
13	5.1	20.7	13.50	20.50	31.13
14	5.8	26.9	17.96	27.27	41.41
15	6.7	35.5	23.36	35.46	53.82
16	8.0	49.6	29.70	45.08	68.43
17	8.5	58.7	36.97	56.11	85.17
18	9.0	63.3	45.09	68.43	103.87
19	10.8	2.70	53.93	81.86	124.25
20	11.3	100.1	63.34	96.14	145.92
21	12.1	115.5	73.11	110.97	168.43
22	12.5	124.4	83.02	126.01	191.25
23	13.4	140.3	92.83	140.90	213.85
24	14.7	168.4	102.32	155.29	235.69
25	15.0	171.9	111.27	168.88	256.31
26	15.4	190.2	119.52	181.39	275.29
27	15.6	193.1	126.91	192.61	292.33
28	16.2	210.4	133.36	202.40	307.19
29	16.6	218.1	138.82	210.69	319.77
30	16.8	226.0	143.28	217.47	330.05
31	17.4	239.2	146.79	222.79	338.13
32	17.4	235.2	149.40	226.76	344.17
33	17.0	231.7	151.24	229.54	348.38
34	17.3	237.7	152.40	231.30	351.05
35	17.6	241.9	153.03	232.26	352.50
36	17.1	230.8	153.27	232.63	353.06
37	17.4	235.7	153.27	232.63	353.10
38	17.5	238.1	153.16	232.51	352.96
39	17.5	241.1	153.10	232.48	353.03
40	17.8	252.0	153.21	232.78	353.68

Gestational Age (Weeks)	Diameter (Mean)	Area (Mean)	Area-Percentiles
Gestational Age (Weeks)	Diameter (Mean)	Area (Mean)	10th	50th	90th
12	4.5	16.5	9.89	15.03	22.84
13	5.1	20.7	13.50	20.50	31.13
14	5.8	26.9	17.96	27.27	41.41
15	6.7	35.5	23.36	35.46	53.82
16	8.0	49.6	29.70	45.08	68.43
17	8.5	58.7	36.97	56.11	85.17
18	9.0	63.3	45.09	68.43	103.87
19	10.8	2.70	53.93	81.86	124.25
20	11.3	100.1	63.34	96.14	145.92
21	12.1	115.5	73.11	110.97	168.43
22	12.5	124.4	83.02	126.01	191.25
23	13.4	140.3	92.83	140.90	213.85
24	14.7	168.4	102.32	155.29	235.69
25	15.0	171.9	111.27	168.88	256.31
26	15.4	190.2	119.52	181.39	275.29
27	15.6	193.1	126.91	192.61	292.33
28	16.2	210.4	133.36	202.40	307.19
29	16.6	218.1	138.82	210.69	319.77
30	16.8	226.0	143.28	217.47	330.05
31	17.4	239.2	146.79	222.79	338.13
32	17.4	235.2	149.40	226.76	344.17
33	17.0	231.7	151.24	229.54	348.38
34	17.3	237.7	152.40	231.30	351.05
35	17.6	241.9	153.03	232.26	352.50
36	17.1	230.8	153.27	232.63	353.06
37	17.4	235.7	153.27	232.63	353.10
38	17.5	238.1	153.16	232.51	352.96
39	17.5	241.1	153.10	232.48	353.03
40	17.8	252.0	153.21	232.78	353.68

Determined by sonography and generated from a predominantly white Brazilian population between 2005 and 2006.

Data from reference 3.

Appendix C References

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Fitzgerald

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APPENDIX D: UMBILICAL CORD COILING INDEX

UMBILICAL CORD COILING INDEX (LISTED AS COILS PER CM)

Population	10th Percentile	Mean	90th Percentile	Methods and Sample Type	Year
India (1)	0.26	0.36	0.46	Ultrasound measurements 22-24 weeks GA^a	2012-2013
Israel (2)		0.44		Antenatal by ultrasound within 24 hrs of birth	1995
Israel (2)		0.28		Postnatal	1995
Netherlands (3)	0.07	0.17	0.30	39.8 weeks mean GA	2001
United Kingdom (4)		0.2		Unfixed measurements 37-42 weeks GA	2007-08
USA (AZ and CA) (5)	0.01	0.21	0.30	38.8 weeks mean GA	1992

Population	10th Percentile	Mean	90th Percentile	Methods and Sample Type	Year
India (1)	0.26	0.36	0.46	Ultrasound measurements 22-24 weeks GA^a	2012-2013
Israel (2)		0.44		Antenatal by ultrasound within 24 hrs of birth	1995
Israel (2)		0.28		Postnatal	1995
Netherlands (3)	0.07	0.17	0.30	39.8 weeks mean GA	2001
United Kingdom (4)		0.2		Unfixed measurements 37-42 weeks GA	2007-08
USA (AZ and CA) (5)	0.01	0.21	0.30	38.8 weeks mean GA	1992

GA = gestational age.

Appendix D References

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Nanda

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APPENDIX E: BIRTH WEIGHT/PLACENTAL WEIGHT RATIO STANDARDS

Appendix E-1

BIRTH WEIGHT:PLACENTAL WEIGHT (UNTRIMMED) RATIO PERCENTILES BY GESTATIONAL AGE^a,b

Gestational Age (Weeks)	Percentiles for Birth Weight: Placental Weight Ratio (Female and Male Births)
	3rd		10th		50th		90th		97th
	F	M	F	M	F	M	F	M	F	M
24	1.68	1.81	1.95	2.06	2.65	2.71	3.58	3.62	4.12	4.17
25	1.81	1.93	2.09	2.20	2.81	2.87	3.79	3.82	4.35	4.39
26	1.95	2.07	2.24	2.35	2.99	3.05	4.00	4.03	4.59	4.61
27	2.10	2.21	2.40	2.50	3.16	3.24	4.22	4.26	4.83	4.85
28	2.26	2.36	2.58	2.67	3.36	3.44	4.44	4.46	5.08	5.10
29	2.43	2.53	2.76	2.85	3.56	3.64	4.67	4.69	5.32	5.35
30	2.62	2.70	2.96	3.03	3.77	3.85	4.90	4.95	5.59	5.59
31	2.82	2.87	3.16	3.22	3.98	4.07	5.15	5.18	5.85	5.85
32	3.01	3.05	3.38	3.41	4.20	4.27	5.41	5.43	6.10	6.10
33	3.22	3.23	3.58	3.61	4.41	4.48	5.62	5.65	6.37	6.37
34	3.41	3.40	3.80	3.80	4.63	4.69	5.85	5.88	6.58	6.58
35	3.61	3.56	4.00	3.98	4.83	4.90	6.06	6.10	6.80	6.80
36	3.79	3.72	4.20	4.15	5.00	5.08	6.25	6.29	6.99	7.04
37	3.95	3.85	4.37	4.29	5.18	5.24	6.41	6.49	7.14	7.19
38	4.07	3.95	4.50	4.42	5.32	5.38	6.54	6.62	7.30	7.35
39	4.17	4.03	4.61	4.50	5.43	5.46	6.67	6.76	7.35	7.52
40	4.20	4.08	4.67	4.57	5.49	5.52	6.71	6.80	7.41	7.58
41	4.20	4.10	4.69	4.59	5.52	5.56	6.76	6.85	7.41	7.63
42	4.15	4.07	4.67	4.57	5.52	5.56	6.71	6.85	7.35	7.69
43	4.07	4.00	4.61	4.50	5.49	5.52	6.67	6.85	7.30	7.63
44	3.94	3.91	4.50	4.42	5.41	5.43	6.58	6.76	7.19	7.58

Gestational Age (Weeks)	Percentiles for Birth Weight: Placental Weight Ratio (Female and Male Births)
	3rd		10th		50th		90th		97th
	F	M	F	M	F	M	F	M	F	M
24	1.68	1.81	1.95	2.06	2.65	2.71	3.58	3.62	4.12	4.17
25	1.81	1.93	2.09	2.20	2.81	2.87	3.79	3.82	4.35	4.39
26	1.95	2.07	2.24	2.35	2.99	3.05	4.00	4.03	4.59	4.61
27	2.10	2.21	2.40	2.50	3.16	3.24	4.22	4.26	4.83	4.85
28	2.26	2.36	2.58	2.67	3.36	3.44	4.44	4.46	5.08	5.10
29	2.43	2.53	2.76	2.85	3.56	3.64	4.67	4.69	5.32	5.35
30	2.62	2.70	2.96	3.03	3.77	3.85	4.90	4.95	5.59	5.59
31	2.82	2.87	3.16	3.22	3.98	4.07	5.15	5.18	5.85	5.85
32	3.01	3.05	3.38	3.41	4.20	4.27	5.41	5.43	6.10	6.10
33	3.22	3.23	3.58	3.61	4.41	4.48	5.62	5.65	6.37	6.37
34	3.41	3.40	3.80	3.80	4.63	4.69	5.85	5.88	6.58	6.58
35	3.61	3.56	4.00	3.98	4.83	4.90	6.06	6.10	6.80	6.80
36	3.79	3.72	4.20	4.15	5.00	5.08	6.25	6.29	6.99	7.04
37	3.95	3.85	4.37	4.29	5.18	5.24	6.41	6.49	7.14	7.19
38	4.07	3.95	4.50	4.42	5.32	5.38	6.54	6.62	7.30	7.35
39	4.17	4.03	4.61	4.50	5.43	5.46	6.67	6.76	7.35	7.52
40	4.20	4.08	4.67	4.57	5.49	5.52	6.71	6.80	7.41	7.58
41	4.20	4.10	4.69	4.59	5.52	5.56	6.76	6.85	7.41	7.63
42	4.15	4.07	4.67	4.57	5.52	5.56	6.71	6.85	7.35	7.69
43	4.07	4.00	4.61	4.50	5.49	5.52	6.67	6.85	7.30	7.63
44	3.94	3.91	4.50	4.42	5.41	5.43	6.58	6.76	7.19	7.58

Generated from a Norwegian population between 1999-2002.

Data from reference 1.

Appendix E-2

FETAL:PLACENTAL WEIGHT RATIO^a FOR FEMALE BIRTHS IN THE JAPANESE POPULATION (BETWEEN 2001 AND 2002) ACCORDING TO MATERNAL PARITY^b

Gestational Age (Weeks)	Percentile
	10th		50th		90th
	P^c	M	P	M	P	M
22	1.31	1.33	1.92	1.89	2.83	3.14
23	1.43	1.45	2.09	2.06	3.03	3.28
24	1.56	1.57	2.25	2.23	3.22	3.42
25	1.69	1.69	2.42	2.40	3.41	3.57
26	1.82	1.82	2.59	2.56	3.60	3.71
27	1.95	1.95	2.76	2.74	3.79	3.87
28	2.10	2.08	2.93	2.91	3.98	4.02
29	2.25	2.23	3.12	3.10	4.18	4.19
30	2.41	2.39	3.30	3.29	4.38	4.37
31	2.57	2.56	3.49	3.49	4.58	4.57
32	2.75	2.75	3.69	3.70	4.80	4.78
33	2.95	2.95	3.90	3.92	5.02	5.00
34	3.15	3.16	4.11	4.14	5.24	5.23
35	3.37	3.39	4.33	4.38	5.47	5.48
36	3.59	3.63	4.55	4.61	5.70	5.73
37	3.82	3.86	4.78	4.85	5.93	5.98
38	4.04	4.08	4.98	5.06	6.14	6.20
39	4.23	4.27	5.15	5.23	6.30	6.38
40	4.36	4.40	5.26	5.35	6.40	6.48
41	4.44	4.49	5.33	5.42	6.45	6.54

Gestational Age (Weeks)	Percentile
	10th		50th		90th
	P^c	M	P	M	P	M
22	1.31	1.33	1.92	1.89	2.83	3.14
23	1.43	1.45	2.09	2.06	3.03	3.28
24	1.56	1.57	2.25	2.23	3.22	3.42
25	1.69	1.69	2.42	2.40	3.41	3.57
26	1.82	1.82	2.59	2.56	3.60	3.71
27	1.95	1.95	2.76	2.74	3.79	3.87
28	2.10	2.08	2.93	2.91	3.98	4.02
29	2.25	2.23	3.12	3.10	4.18	4.19
30	2.41	2.39	3.30	3.29	4.38	4.37
31	2.57	2.56	3.49	3.49	4.58	4.57
32	2.75	2.75	3.69	3.70	4.80	4.78
33	2.95	2.95	3.90	3.92	5.02	5.00
34	3.15	3.16	4.11	4.14	5.24	5.23
35	3.37	3.39	4.33	4.38	5.47	5.48
36	3.59	3.63	4.55	4.61	5.70	5.73
37	3.82	3.86	4.78	4.85	5.93	5.98
38	4.04	4.08	4.98	5.06	6.14	6.20
39	4.23	4.27	5.15	5.23	6.30	6.38
40	4.36	4.40	5.26	5.35	6.40	6.48
41	4.44	4.49	5.33	5.42	6.45	6.54

The placental weight was taken in the unfixed and untrimmed state.

Data from reference 2.

P = primiparity; M = multiparity.

Appendix E-3

FETAL:PLACENTAL WEIGHT RATIO^a FOR MALE BIRTHS IN THE JAPANESE POPULATION (BETWEEN 2001 AND 2002) ACCORDING TO MATERNAL PARITY^b

Gestational Age (Weeks)	Percentile
	10th		50th		90th
	P^c	M	P	M	P	M
22	1.49	1.29	2.13	1.90	3.15	2.70
23	1.60	1.44	2.28	2.09	3.31	2.95
24	1.71	1.59	2.42	2.29	3.46	3.19
25	1.83	1.75	2.57	2.48	3.61	3.43
26	1.95	1.91	2.73	2.67	3.77	3.66
27	2.08	2.07	2.88	2.86	3.94	3.89
28	2.22	2.24	3.05	3.05	4.11	4.10
29	2.36	2.41	3.22	3.24	4.28	4.31
30	2.52	2.58	3.40	3.43	4.47	4.52
31	2.70	2.76	3.60	3.63	4.68	4.72
32	2.88	2.94	3.81	3.82	4.90	4.93
33	3.08	3.13	4.02	4.03	5.12	5.14
34	3.29	3.33	4.25	4.24	5.36	5.36
35	3.51	3.54	4.47	4.47	5.59	5.60
36	3.73	3.76	4.69	4.70	5.82	5.85
37	3.94	3.99	4.91	4.94	6.05	6.09
38	4.14	4.2	5.11	5.16	6.25	6.32
39	4.30	4.36	5.26	5.32	6.41	6.48
40	4.42	4.47	5.36	5.43	6.50	6.58
41	4.50	4.55	5.43	5.50	6.56	6.64

Gestational Age (Weeks)	Percentile
	10th		50th		90th
	P^c	M	P	M	P	M
22	1.49	1.29	2.13	1.90	3.15	2.70
23	1.60	1.44	2.28	2.09	3.31	2.95
24	1.71	1.59	2.42	2.29	3.46	3.19
25	1.83	1.75	2.57	2.48	3.61	3.43
26	1.95	1.91	2.73	2.67	3.77	3.66
27	2.08	2.07	2.88	2.86	3.94	3.89
28	2.22	2.24	3.05	3.05	4.11	4.10
29	2.36	2.41	3.22	3.24	4.28	4.31
30	2.52	2.58	3.40	3.43	4.47	4.52
31	2.70	2.76	3.60	3.63	4.68	4.72
32	2.88	2.94	3.81	3.82	4.90	4.93
33	3.08	3.13	4.02	4.03	5.12	5.14
34	3.29	3.33	4.25	4.24	5.36	5.36
35	3.51	3.54	4.47	4.47	5.59	5.60
36	3.73	3.76	4.69	4.70	5.82	5.85
37	3.94	3.99	4.91	4.94	6.05	6.09
38	4.14	4.2	5.11	5.16	6.25	6.32
39	4.30	4.36	5.26	5.32	6.41	6.48
40	4.42	4.47	5.36	5.43	6.50	6.58
41	4.50	4.55	5.43	5.50	6.56	6.64

The placental weight was taken in the unfixed and untrimmed state.

Data from reference 2.

P = primiparity; M = multiparity.

Appendix E-4

FITTED PLACENTAL WEIGHT (UNFIXED AND UNTRIMMED):BIRTH WEIGHT RATIO STANDARDS^a FOR TERM PLACENTAS GENERATED FROM A HEALTHY SWISS POPULATION BETWEEN 1995 AND 2002

Gestational Age (Weeks)	Percentile
Gestational Age (Weeks)	5th	50th	95th
37 + 0 to 37 + 6	13.2 (13.0-13.3)	17.6 (17.4-17.7)	23.4 (23.3-23.6)
38 + 0 to 38 + 6	12.9 (12.8-13.0)	17.0 (16.9-17.2)	22.5 (22.3-22.6)
39 + 0 to 39 + 6	12.7 (12.5-12.8)	16.5 (16.4-16.7)	21.5 (21.4-21.7)
40 + 0 to 40 + 6	12.5 (12.3-12.6)	16.1 (15.9-16.2)	20.7 (20.6-20.9)
41 + 0 to 41 + 6	12.2 (12.1-12.4)	15.6 (15.5-15.7)	19.9 (19.7-20.0)

Gestational Age (Weeks)	Percentile
Gestational Age (Weeks)	5th	50th	95th
37 + 0 to 37 + 6	13.2 (13.0-13.3)	17.6 (17.4-17.7)	23.4 (23.3-23.6)
38 + 0 to 38 + 6	12.9 (12.8-13.0)	17.0 (16.9-17.2)	22.5 (22.3-22.6)
39 + 0 to 39 + 6	12.7 (12.5-12.8)	16.5 (16.4-16.7)	21.5 (21.4-21.7)
40 + 0 to 40 + 6	12.5 (12.3-12.6)	16.1 (15.9-16.2)	20.7 (20.6-20.9)
41 + 0 to 41 + 6	12.2 (12.1-12.4)	15.6 (15.5-15.7)	19.9 (19.7-20.0)

Ratios are multiplied by 100.

Data from reference 3.

Appendix E-5

BIRTH WEIGHT, PLACENTAL WEIGHT^a, AND FETAL:PLACENTAL WEIGHT RATIO IN MONOCHORIONIC AND DICHORIONIC TWINS GENERATED FROM A NORTH EASTERN UNITED STATES POPULATION BETWEEN 2009 AND 2013^b,c

Gestational Age (Weeks)	Birth Weight (g)		Placental Weight (g)		Fetal:Placental Weight Ratio
Gestational Age (Weeks)	Monochorionic	Dichorionic	Monochorionic	Dichorionic	Monochorionic	Dichorionic
25-27	845 ± 156	972 ± 55	186 ± 89	153 ± 27	5.28 ± 2.12	6.48 ± 1.09
28-30	1211 ± 277	1426 ± 268	219 ± 69	265 ± 71	5.91 ± 1.66	5.67 ± 1.64
31-33	1682 ± 332	1825 ± 336	296 ± 102	332 ± 83	6.29 ± 2.34	5.68 ± 1.10
34-36	2252 ± 352	242 3 ± 333	365 ± 104	388 ± 89	6.54 ± 1.73	6.43 ± 1.10
37-39	2621 ± 341	2835 ± 317	399 ± 95	419 ± 85	6.86 ± 1.51	6.99 ± 1.36

Gestational Age (Weeks)	Birth Weight (g)		Placental Weight (g)		Fetal:Placental Weight Ratio
Gestational Age (Weeks)	Monochorionic	Dichorionic	Monochorionic	Dichorionic	Monochorionic	Dichorionic
25-27	845 ± 156	972 ± 55	186 ± 89	153 ± 27	5.28 ± 2.12	6.48 ± 1.09
28-30	1211 ± 277	1426 ± 268	219 ± 69	265 ± 71	5.91 ± 1.66	5.67 ± 1.64
31-33	1682 ± 332	1825 ± 336	296 ± 102	332 ± 83	6.29 ± 2.34	5.68 ± 1.10
34-36	2252 ± 352	242 3 ± 333	365 ± 104	388 ± 89	6.54 ± 1.73	6.43 ± 1.10
37-39	2621 ± 341	2835 ± 317	399 ± 95	419 ± 85	6.86 ± 1.51	6.99 ± 1.36

Unfixed and trimmed.

Data from reference 4.

Values represented as Mean ± Standard deviation.

Appendix E References

Thompson

Irgens

Skjaerven

Rassussen

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APPENDIX F: REPORTING

Suggested standard placental reporting template:

Mature/immature placenta (weight in grams, fixed/fresh; percentile for stated gestational age)
Pertinent positive placental findings
Pertinent negative placental findings
Note: as required for diagnostic criteria
Comment: if helpful for clinicopathologic correlation
References: as needed

Examples:

Preterm birth:
- Immature placenta (270g fresh trimmed weight, approximately the 50th percentile for 28 weeks gestational age).
- Acute chorioamnionitis (maternal stage 2, grade 2) with fetal inflammatory response (fetal stage 2, grade 1), see note.
- Features consistent with a marginal placental abruption:
  - Marginal hematoma, 6 cm in greatest dimension.
  - Inter- and intravillous hemorrhage.
References:
- Khong TY, Mooney EE, Ariel I, et al. Sampling and definitions of placental lesions: Amsterdam Placental Workshop Group consensus statement. Arch Pathol Lab Med 2016;140:698-713.
- Redline RW, Faye-Petersen O, Heller D, et al. Amniotic infection syndrome: nosology and reproducibility of placental reaction patterns. Pediatr Dev Pathol 2003;6:435-48.
Preterm preeclampsia with severe features:
- Mature placenta (260g fresh trimmed weight, approximately the 3rd percentile for 32 weeks gestational age).
- Maternal vascular malperfusion (see comment):
  - Small placenta by weight.
  - Thin umbilical cord (0.6 cm in diameter, expect greater than or equal to 0.8 cm for 32 weeks; gestational age)
  - Decidual arteriopathy: fibrinoid necrosis with acute atherosis.
  - Patchy distal villous hypoplasia.
  - Multiple placental infarcts, in aggregate estimated to be ~5% of the placental mass, usual and hypertensive types.
Comment: These features are evidence of placental injury from hypertension.
Fetal growth restriction in a multipara:
- Mature placenta (375g formalin-fixed trimmed weight, less than the 10th percentile for 37 weeks gestational age).
- Recurrent villitis of unknown etiology, high grade, diffuse, with associated avascular villi (fetal vascular malperfusion, high grade, global), see comment.
- Chronic chorioamnionitis, stage 2, grade 1.
- Chronic deciduitis, grade 1.
Comment: We reviewed the previous placental pathology from 2016 which also showed villitis of unknown etiology (VUE) but was low grade, at 38 weeks without fetal growth restriction, therefore this is a recurrent VUE presenting at a higher grade and complicated with fetal growth restriction (FGR). VUE has a recurrence risk on the order of 10-15% and is associated with FGR. Villitis with accompanying avascular villi has been associated with fetal/neonatal morbidity.
References:
- Kim CJ, Romero R, Kusanovic JP, et al. The frequency, clinical significance, and pathological features of chronic chorioamnionitis: a lesion associated with spontaneous preterm birth. Mod Pathol 2010;23:1000-11.
- Maroun LL, Mathiesen L, Hedegaard M, Knudsen LE, Larsen LG. Pathologic evaluation of normal and perfused term placental tissue. Pediatr Dev Pathol 2014;17:330-8.
- Redline RW. Severe fetal placental vascular lesions in term infants with neurologic impairment. Am J Obstet Gynecol 2005;192:452-7.
- Redline RW. Villitis of unknown etiology: noninfectious chronic villitis in the placenta. Hum Pathol 2007;38:1439-46.
Intrauterine fetal demise at 41 weeks:
- Mature placenta (450g fresh trimmed weight, approximately the 10th percentile for 41 weeks gestational age).
- Long umbilical cord (83 cm).
- Hypercoiled and linked pattern umbilical cord.
- Fetal vascular malperfusion, high grade, segmental/complete pattern, with stem villous vascular obliteration and avascular villi, see comment.
- Autopsy consent declined.
Comment: Although one cannot completely exclude postmortem changes causing the fetal vascular malperfusion, due to the spatial and temporal heterogeneity of the findings we favor that the fetal vascular malperfusion occurred antemortem and therefore it can be implicated as the cause of death in this case. The long, hypercoiled, and linked pattern umbilical cord is the likely cause of the fetal vascular malperfusion.
Twin gestation with hydrops fetalis of the presenting twin and small for gestational age of the nonpresenting twin:
- Fused diamniotic dichorionic twin placenta (630g combined fresh trimmed weight, approximately the 25th percentile for 34 weeks gestational age), see note.
- Twin A (one cord clamp): immature placenta, approximately 80% of the combined placental disc.
- Marginal insertion of the umbilical cord.
- Hydrops placentalis:
  - Giant chorangioma, 5cm in maximal dimension.
  - Multifocal villous edema.
  - Chorangiosis.
  - Increased circulating nucleated fetal red blood cells.
  - Twin B (two cord clamps): mature placenta, approximately 20% of the combined placental disc.
- Velamentous insertion of the umbilical cord.
- Single umbilical artery.
Note: Zygosity cannot be determined by placental examination alone with dichorionic placentation.
Comment: The giant chorangioma is the likely etiology of the fetal hydrops of twin A, causing high output heart failure and/or anemia from vascular steal. A single umbilical artery has been associated with aneuploidy, structural anomalies, abnormal cord insertions, and growth restriction.
Manual extraction of the placenta at term:
- Disrupted mature placenta (400 g formalin-fixed trimmed weight, would be less than the 10th percentile for 39 3/7 weeks gestational age if complete).
- Basal plate myometrial fibers (stage 2), focal, 1 mm in maximal dimension, see note.
Note: Stage 2 basal plate myometrial fibers (BPMF) may be an incidental finding, but may confirm noninvasive placenta accreta spectrum (PAS) in the appropriate clinical setting and may contribute to increased risk of PAS in subsequent pregnancies. Stage 1 BPMF is likely an incidental finding. We use the Society of Pediatric Pathology Task Force on Placenta Accreta Spectrum staging system.
Meconium-stained amniotic fluid in a postdates pregnancy:
- Heavy mature placenta (700g fresh trimmed weight, greater than the 90th percentile for 41 5/7 weeks gestational age).
- Pigment-laden macrophages in the chorion and in umbilical cord Wharton's jelly consistent with meconium.
- Meconium-associated myonecrosis of the umbilical arteries, see comment.
Comment: This is a rare finding in which the vascular muscle undergoes apoptosis secondary to meconium exposure/ toxicity. In retrospective studies this finding has been associated with neonatal morbidity, prospective studies have not been reported. These findings were discussed with Dr. Pediatrician on October 25, 2018 at 10 a.m.
[For in-house cases I prefer to call the pediatrician personally and discuss the findings and implications and not put in the comment about morbidity; for consult cases I put this comment in and also call the consulting pathologist. See Appendix G for critical values.]

Appendix F References

Altshuler

Arizawa

Molnar-Nadasdy

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Obstet Gynecol

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(

Pt 1

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APPENDIX G: CRITICAL VALUES

APPENDIX G-1:

GROSS FINDINGS OF CRITICAL VALUE

Finding	Who to Call	What to Report
Placental abscesses (chapter 8-5)	Pediatrician/neonatologist	High suspicion of listerial placentitis or other rare placental infections
Umbilical cord abscesses (chapter 4-10)	Pediatrician/neonatologist	High suspicion of andida placentitis
Diffuse chorioamniotic hemosiderosis (chapter 5-4)	Pediatrician/neonatologist	Association with pulmonary and neurologic complications, increased neonatal mortality
Massive perivillous fibrin deposition/maternal floor infarct (chapter 8-7)	Pediatrician/neonatologist and obstetric provider	Rule out infant renal disorders or metabolic disease; high occurrence risk; association with maternal thrombophilia and autoimmune disease
Placental mesenchymal dysplasia (chapter 8-2)	Pediatrician/neonatologist	Association with Beckwith-Wiedemann syndrome and congenital/pediatric neoplasia
Umbilical cord ulceration (chapters 4-10 and 4-12)	Pediatrician/neonatologist	Rule out intestinal atresia or meconium- associated myonecrosis

Finding	Who to Call	What to Report
Placental abscesses (chapter 8-5)	Pediatrician/neonatologist	High suspicion of listerial placentitis or other rare placental infections
Umbilical cord abscesses (chapter 4-10)	Pediatrician/neonatologist	High suspicion of andida placentitis
Diffuse chorioamniotic hemosiderosis (chapter 5-4)	Pediatrician/neonatologist	Association with pulmonary and neurologic complications, increased neonatal mortality
Massive perivillous fibrin deposition/maternal floor infarct (chapter 8-7)	Pediatrician/neonatologist and obstetric provider	Rule out infant renal disorders or metabolic disease; high occurrence risk; association with maternal thrombophilia and autoimmune disease
Placental mesenchymal dysplasia (chapter 8-2)	Pediatrician/neonatologist	Association with Beckwith-Wiedemann syndrome and congenital/pediatric neoplasia
Umbilical cord ulceration (chapters 4-10 and 4-12)	Pediatrician/neonatologist	Rule out intestinal atresia or meconium- associated myonecrosis

APPENDIX G-2:

MICROSCOPIC FINDINGS OF CRITICAL VALUE

Finding	Who to Call	What to Report
Confirmation of the gross findings of critical value	As per G-1	Confirmation of findings reported, as per G-1
Meconium-associated myonecrosis (chapter 4-12)	Pediatrician/neonatologist	Retrospective studies show association with neurocompromise – consider increased surveillance
Fetal malignancy involving placenta (chapter 8-8)	Pediatrician/neonatologist Obstetric provider	Specify malignancy Possibility of maternal metastasis
Maternal malignancy metastatic to placenta (chapter 8-8)	Pediatrician/neonatologist Obstetric provider	Possibility of infant metastasis Specify malignancy, high mortality rate
Intraplacental choriocarcinoma (chapter 8-8)	Pediatrician/neonatologist Obstetric provider	Possibility of infant metastasis Possibility of metastatic disease, recommend referral to GYN oncologist
Inborn errors of metabolism/lyso- somal storage disorder (chapter 8-10)	Pediatrician/neonatologist	Inborn error but can’t be specific, needs further work-up, recommend genetics consult
Placental mesenchymal dysplasia (chapter 8-2)	Pediatrician/neonatologist	Possibility of Beckwith-Wiedemann syndrome, congenital/pediatric malignancies Infant needs genetic evaluation
Specific infection (chapters 5-5 and 8-5)	Pediatrician/neonatologist Obstetric provider	Evaluation and treatment of infant and mother as clinically indicated
Intravascular organisms (chapter 8-5)	Obstetric provider	Associated with maternal sepsis and mortality risk
Chronic histiocytic intervillositis (chapter 8-7)	Pediatrician/neonatologist obstetric provider	Risk of neonatal alloimmune thrombocytopenia and other neonatal morbidity/mortality; obtain confirmatory maternal Alkphos level association with autoimmune disease high recurrence risk

Finding	Who to Call	What to Report
Confirmation of the gross findings of critical value	As per G-1	Confirmation of findings reported, as per G-1
Meconium-associated myonecrosis (chapter 4-12)	Pediatrician/neonatologist	Retrospective studies show association with neurocompromise – consider increased surveillance
Fetal malignancy involving placenta (chapter 8-8)	Pediatrician/neonatologist Obstetric provider	Specify malignancy Possibility of maternal metastasis
Maternal malignancy metastatic to placenta (chapter 8-8)	Pediatrician/neonatologist Obstetric provider	Possibility of infant metastasis Specify malignancy, high mortality rate
Intraplacental choriocarcinoma (chapter 8-8)	Pediatrician/neonatologist Obstetric provider	Possibility of infant metastasis Possibility of metastatic disease, recommend referral to GYN oncologist
Inborn errors of metabolism/lyso- somal storage disorder (chapter 8-10)	Pediatrician/neonatologist	Inborn error but can’t be specific, needs further work-up, recommend genetics consult
Placental mesenchymal dysplasia (chapter 8-2)	Pediatrician/neonatologist	Possibility of Beckwith-Wiedemann syndrome, congenital/pediatric malignancies Infant needs genetic evaluation
Specific infection (chapters 5-5 and 8-5)	Pediatrician/neonatologist Obstetric provider	Evaluation and treatment of infant and mother as clinically indicated
Intravascular organisms (chapter 8-5)	Obstetric provider	Associated with maternal sepsis and mortality risk
Chronic histiocytic intervillositis (chapter 8-7)	Pediatrician/neonatologist obstetric provider	Risk of neonatal alloimmune thrombocytopenia and other neonatal morbidity/mortality; obtain confirmatory maternal Alkphos level association with autoimmune disease high recurrence risk

APPENDIX H: PLACENTA GROSS DICTATION TEMPLATES AND EXAMPLES

Appendix H-1

The specimen is received fresh labeled “placenta” and consists of a (intact/disrupted, shape) singleton placenta.

Umbilical cord:

Insertion: _____________

Length: _____________

Diameter: _____________

Total number of coils: _____________

Coil direction: _____________

Color: _____________

Other findings: _____________

Membranes:

Insertion: _____________

Color: _____________

Other findings: _____________

Trimmed placental weight:

Disc measurements: _______

Fetal surface findings:

Color: _____________

Lesions: _____________

Other findings: _____________

Maternal surface:

Intactness: _____________

Blood clot: _____________

Other findings: _____________

Parenchyma:

Color and texture: _____________

Lesions: _____________

Summary of findings:

Section Code:

A1: Membrane rolls and umbilical cord

A2-A4: Full-thickness parenchyma

A5-A_: Lesions

Appendix H-2

The specimen is received fresh labeled “placenta” and consists of an oval singleton placenta.

Umbilical cord:

Insertion: Eccentric, 4.2 cm from the disc margin

Length: 47.5cm

Diameter: 1.2 cm

Total number of coils: 9

Coil direction: Left

Color: Tan-white with vague pale green discoloration

Other findings: None

Membranes:

Insertion: 60 % marginate and 40% circummarginate

Color: Tan-pink and semitranslucent with vague pale green discoloration

Other findings: There are small caliber intact vessels traversing the membranes over a maximum distance of 4.7 cm

Trimmed placental weight: 510 g, corresponding to the approximate 50^th percentile for gestational age of 40 weeks

Disc measurements: 22.5 x 19.8 x 1.5 cm

Fetal surface findings:

Color: Gray-blue with vague green discoloration

Lesions: There are scattered minute gray-white plaque-like lesions adjacent to the umbilical cord insertion site, and a 1.4 x 1.0 x 0.4-cm cyst at the periphery which contains clear fluid

Other findings: The surface appears well vascularized with small to medium caliber vessels; there is scant fibrin deposition at the periphery associated with circummarginate membrane insertion

Maternal surface:

Intactness: Focally torn cotyledons which reapproximate and appear complete

Blood clot: There is a 3.0 x 2.3 x 0.3-cm focus of loosely to moderately adherent blood clot at the periphery

Other findings: There are scant tan-yellow calcific deposits

Parenchyma:

Color and texture: Dark red and soft to spongy

Lesions: There is a 1.0 x 0.8 x 0.8-cm peripheral, wedge-shaped, tan rubbery lesion and a 2.0 x 1.6 x 0.9-cm tan-red laminated lesion in the center of the disc; the lesions comprise less than 10% of the placental parenchyma

Summary of findings: A 510 g singleton placenta corresponding to the approximate 50^th percentile for gestational age of 40 weeks, which exhibits vague green discoloration of the fetal surface, membranes, and umbilical cord and has a torn but complete appearing maternal surface. There are small caliber intact vessels traversing the membranes and 2 parenchymal lesions, which comprise less than 10% of the disc.

Section Code:

A1: Umbilical cord and membrane roll to include membranous vessels

A2-A3: Full-thickness parenchyma

A4: Full-thickness parenchyma to include loosely adherent blood clot

A5: Peripheral parenchymal lesion

A6: Central parenchymal lesion

Appendix H-3

The specimen is received fresh labeled “placenta” and consists of a fused/separate twin placenta with cords oriented to birth order by number of clamps. Placenta A has ___cord clamp(s) and Placenta B has ___ cord clamp(s). The dividing membrane is ___ . (The vascular equator divides the placenta ___% to Placenta A and ___% to Placenta B. Vascular anastomoses are/are not identified and consist of ___ artery-artery, vein-vein, Placenta A artery to Placenta B vein, and___ Placenta B Artery to Placenta A Vein anastomoses.)^*

Placenta A, __________ Cord Clamp(s), __________ % of fused disc mass:

Umbilical cord:

Insertion: _____________

Length: _____________

Diameter: _____________

Total number of coils: _____________

Coil direction: _____________

Color: _____________

Other findings: _____________

Membranes:

Insertion: _____________

Color: _____________

Other findings: _____________

Trimmed placental weight:

Disc measurements: _____________^*

Fetal surface findings:

Color: _____________

Lesions: _____________

Other findings: _____________

Maternal surface:

Intactness: _____________

Blood clot: _____________

Other findings: _____________

Parenchyma:

Color and texture: _____________

Lesions: _____________

Placenta B, ______ Cord Clamp(s), ____ % of fused disc mass

Umbilical cord:

Insertion: _____________

Length: _____________

Diameter: _____________

Total number of coils: _____________

Coil direction: _____________

Color: _____________

Other findings: _____________

Membranes:

Insertion: _____________

Color: _____________

Other findings: _____________

Trimmed placental weight:

Disc measurements: _________ ^*

Fetal surface findings:

Color: _____________

Lesions: _____________

Other findings: _____________

Maternal surface:

Intactness: _____________

Blood clot: _____________

Other findings: _____________

Parenchyma:

Color and texture: _____________

Lesions: _____________

Combined trimmed placental weight:

Fused disc measurement: ^*

Summary of findings:

Section Code:

A1: Placenta A: Membrane rolls and Umbilical cord

A2-A4: Placenta A: Full-thickness parenchyma

A5: Placenta A: Lesions

A6: Placenta B: Membrane rolls and umbilical cord

A7-A9: Placenta B: Full-thickness parenchyma

A10: Placenta B: Lesions

A11: Dividing membranes

Include or omit these sections as appropriate. Fused placentas will only have a combined weight and measurement. Separate discs will have individual weight and measurements, and a combined weight. Vascular anastomoses will not be present in separate discs.

Appendix H-4

The specimen is received fresh labeled “placenta” and consists of a fused twin placenta with cords oriented to birth order by number of clamps. Placenta A has 1 cord clamp and Placenta B has 2 cord clamps. The dividing membrane is thin and transparent, and the vascular equator divides the placenta 40% to Placenta A and 60% to Placenta B. Examination of the chorionic plate with the help of gentle palpation reveals one vein-vein, and two artery-artery vascular anastomoses.

Placenta A: 1 cord clamp, 40% of fused disc mass

Umbilical cord:

Insertion: Marginal

Length: 50.5 cm

Diameter: 1.3 cm

Total number of coils: 27

Coil direction: Left

Color: Tan-white

Other findings: There is a loose true knot 30.5 cm from the placental insertion site

Membranes:

Insertion: 70% marginate, 30% circummarginate

Color: Tan-pink and semitranslucent

Other findings: There is a 3.5 x 1.2 x 0.2-cm gray-brown focus adjacent to the circummarginate insertion, consistent with old blood clot, and a large caliber intact vessel traversing the membranes over a maximum distance of 6.3 cm

Fetal surface findings:

Color: Blue-purple

Lesions: None identified

Other findings: Well-developed small caliber vessels

Maternal surface:

Intactness: Complete and intact cotyledons

Blood clot: Scant loosely attached dark red blood clot

Other findings: Scattered tan-yellow calcific deposits

Parenchyma:

Color and texture: Red and soft to spongy

Lesions: None identified

Placenta B: 2 cord clamps 60% of fused disc mass

Umbilical cord:

Insertion: Eccentric, 6.0 cm from the disc margin

Length: 40.8 cm

Diameter: 1.5 cm

Total number of coils: 10

Coil direction: Left

Color: White

Other findings: None

Membranes:

Insertion: 100% marginate

Color: Tan-pink and semitranslucent

Other findings: None

Fetal surface findings:

Color: Gray-blue

Lesions: A 2.0 x 1.3-cm focus of ovoid fibrin deposition adjacent to the cord insertion site

Other findings: Well-developed medium caliber vessels

Maternal surface:

Intactness: Focally torn cotyledons which are reapproximated and appear complete

Blood clot: Scant loosely attached dark red blood clot

Other findings: Scant tan-yellow calcific deposits

Parenchyma:

Color and texture: Dark red and soft to spongy

Lesions: Three peripheral, tan, rubbery, wedge-shaped lesions ranging from 0.7 x 0.6 x 0.5 cm to 2.7 x 1.4 x 1.0 cm

Combined trimmed placental weight: 1100 g, approximate 50^th percentile for gestational age of 36 weeks

Fused disc measurement: 30.3 x 27.8 x 2.0 cm

Additional findings: There is a 5.5 x 3.8 x 1.0-cm aggregate of dark red blood clot within the container and a 10.6 x 1.2 cm segment of tan-white unoriented unremarkable umbilical cord

Summary of findings: The specimen is that of a fused twin placenta with one cord clamp designating Placenta A and two cord clamps designating Placenta B. The fused placental weight is 1100 g corresponding to the approximate 50^th percentile for gestational age of 36 weeks. The dividing membrane is thin and transparent and there is one vein-vein and two artery-artery anastomoses. Placenta A (40% of fused disc mass) exhibits a marginal cord insertion with a large caliber intact vessel traversing the membrane. Placenta A's umbilical cord is hypercoiled with approximately 5 coils/10 cm and has a loose true knot. Placenta B (60% of fused disc mass) exhibits 3 peripheral tan rubbery lesions comprising less than 10% of the disc.

Section Code:

A1: Placenta A: Umbilical cord and membrane rolls to include membranous vessel and old blood clot

A2-A4: Placenta A: Full-thickness parenchyma

A5: Placenta A: Umbilical cord knot

A6: Placenta B: Membrane rolls and umbilical cord

A7-A9: Placenta B: Full-thickness parenchyma

A10: Placenta B: Largest lesions

A11: Placenta B: two small lesions

A12: Dividing membrane

Placenta A: 1 cord clamp, 40% of fused disc mass

Umbilical cord:

Insertion: Marginal

Length: 50.5 cm

Diameter: 1.3 cm

Total number of coils: 27

Coil direction: Left

Color: Tan-white

Other findings: There is a loose true knot 30.5 cm from the placental insertion site

Membranes:

Insertion: 70% marginate, 30% circummarginate

Color: Tan-pink and semitranslucent

Fetal surface findings:

Color: Blue-purple

Lesions: None identified

Other findings: Well-developed small caliber vessels

Maternal surface:

Intactness: Complete and intact cotyledons

Blood clot: Scant loosely attached dark red blood clot

Other findings: Scattered tan-yellow calcific deposits

Parenchyma:

Color and texture: Red and soft to spongy

Lesions: None identified

Placenta B: 2 cord clamps 60% of fused disc mass

Umbilical cord:

Insertion: Eccentric, 6.0 cm from the disc margin

Length: 40.8 cm

Diameter: 1.5 cm

Total number of coils: 10

Coil direction: Left

Color: White

Other findings: None

Membranes:

Insertion: 100% marginate

Color: Tan-pink and semitranslucent

Other findings: None

Fetal surface findings:

Color: Gray-blue

Lesions: A 2.0 x 1.3-cm focus of ovoid fibrin deposition adjacent to the cord insertion site

Other findings: Well-developed medium caliber vessels

Maternal surface:

Intactness: Focally torn cotyledons which are reapproximated and appear complete

Blood clot: Scant loosely attached dark red blood clot

Other findings: Scant tan-yellow calcific deposits

Parenchyma:

Color and texture: Dark red and soft to spongy

Lesions: Three peripheral, tan, rubbery, wedge-shaped lesions ranging from 0.7 x 0.6 x 0.5 cm to 2.7 x 1.4 x 1.0 cm

Combined trimmed placental weight: 1100 g, approximate 50^th percentile for gestational age of 36 weeks

Fused disc measurement: 30.3 x 27.8 x 2.0 cm

Additional findings: There is a 5.5 x 3.8 x 1.0-cm aggregate of dark red blood clot within the container and a 10.6 x 1.2 cm segment of tan-white unoriented unremarkable umbilical cord

Section Code:

A1: Placenta A: Umbilical cord and membrane rolls to include membranous vessel and old blood clot

A2-A4: Placenta A: Full-thickness parenchyma

A5: Placenta A: Umbilical cord knot

A6: Placenta B: Membrane rolls and umbilical cord

A7-A9: Placenta B: Full-thickness parenchyma

A10: Placenta B: Largest lesions

A11: Placenta B: two small lesions

A12: Dividing membrane

Appendix H-5

The triplet placenta template (or other multiple pregnancy) follows the same type of format as a twin. The introductory paragraph is similar and includes a description of the dividing membranes, vascular equator, and anastomoses, for example: The specimen is received fresh labeled “triplet placenta” and consists of a fused triplet placenta in the configuration of the Mercedes-Benz logo. The cords are oriented to birth order by number of clamps and Placenta A has one cord clamp, Placenta B has two cord clamps, and Placenta C has three cord clamps. The dividing membrane between Placenta A and B is thin and transparent and the dividing membranes between Placenta A and C and Placenta B and C are thick and semitranslucent. The vascular equator divides the disc as follows: 40% to Placenta A, 35% to placenta B, 25% to Placenta C. Between Placenta A and B there are two artery to artery vascular anastomoses. There are no anastomoses associated with Placenta C.

After describing the features of each individual placenta (using the same format from the singleton or twin template), describe the combined features, such as weight, measurement, and other additional findings and include a summary of all pertinent pathologic findings, for example:

Combined trimmed placental weight: 1100 g, approximately 50^th percentile for gestational age of 37 weeks

Fused disc measurement: 30.3 x 27.8 x 2.0 cm

Additional findings: There is a 3.0 x 1.7 x 1.0 cm aggregate of dark red blood clot within the container

Summary of findings: The specimen is that of a fused triplet placenta with one cord clamp designating Placenta A, two cord clamps designating Placenta B, and three cord clamps designating Placenta C. The fused placental weight is 1100g corresponding to the approximate 50th percentile for gestational age of 37 weeks. The dividing membrane is thin and transparent between placenta A and B, and there are two artery to artery anastomoses. The dividing membranes between Placenta C and Placenta A, and Placenta C and Placenta B, are thick and semitranslucent. Placenta A (40% of fused disc mass) exhibits a velamentous cord insertion with large caliber intact vessels traversing the membrane over a maximum distance of 8.0 cm. Placenta B (35% of fused disc mass) exhibits a flat umbilical cord which inserts eccentrically. Placenta C (25% of fused disc mass) exhibits 3 parenchymal tan-red laminated lesions ranging from 0.3 to 1.5 cm in greatest dimension which occupy less than 10% of the placental disc. The maternal surface is complete and intact.

Sections for triplets include the following:

Section Code:

A1: Placenta A: Umbilical cord and membrane rolls

A2-A4: Placenta A: Full-thickness parenchyma

A5: Placenta A: Lesions or other findings

A6: Dividing membrane/T zone between Placenta A and B

A7: Placenta B: Umbilical cord and membrane rolls

A8-A10: Placenta B: Full-thickness parenchyma

A11: Placenta B: Lesions or other findings

A12: Dividing membrane between Placenta B and C

A13: Placenta C: Umbilical cord and membrane rolls

A14-A16: Placenta C: Full-thickness parenchyma

A17: Placenta C: Lesions or other findings

A18: Dividing Membrane/T zone between Placenta A and C.

Combined trimmed placental weight: 1100 g, approximately 50^th percentile for gestational age of 37 weeks

Fused disc measurement: 30.3 x 27.8 x 2.0 cm

Additional findings: There is a 3.0 x 1.7 x 1.0 cm aggregate of dark red blood clot within the container

Sections for triplets include the following:

Section Code:

A1: Placenta A: Umbilical cord and membrane rolls

A2-A4: Placenta A: Full-thickness parenchyma

A5: Placenta A: Lesions or other findings

A6: Dividing membrane/T zone between Placenta A and B

A7: Placenta B: Umbilical cord and membrane rolls

A8-A10: Placenta B: Full-thickness parenchyma

A11: Placenta B: Lesions or other findings

A12: Dividing membrane between Placenta B and C

A13: Placenta C: Umbilical cord and membrane rolls

A14-A16: Placenta C: Full-thickness parenchyma

A17: Placenta C: Lesions or other findings

A18: Dividing Membrane/T zone between Placenta A and C.

APPENDIX I: PLACENTAL WEIGHT STANDARDS

APPENDIX I:

ESTIMATING DEATH TO DELIVERY INTERVALS BASED ON PLACENTAL FINDINGS

Finding	Estimated Interval of Retention	Reference
Brown-red discolored umbilical cord^a	≥6 hours	1
>25% vascular smooth muscle degeneration^b	12 to >36 hours	2
Dull pink umbilical cord and chorionic plate/membranes^c	>36 hours	chapters 4-4, 5-4
Multifocal early stem villous vascular luminal abnormalities^d	≥48 hours	3
Extensive stem villous vascular luminal abnormalities^e	≥14 days	3
Extensive avascular villi	≥14 days	3

Finding	Estimated Interval of Retention	Reference
Brown-red discolored umbilical cord^a	≥6 hours	1
>25% vascular smooth muscle degeneration^b	12 to >36 hours	2
Dull pink umbilical cord and chorionic plate/membranes^c	>36 hours	chapters 4-4, 5-4
Multifocal early stem villous vascular luminal abnormalities^d	≥48 hours	3
Extensive stem villous vascular luminal abnormalities^e	≥14 days	3
Extensive avascular villi	≥14 days	3

See figure 3 in chapter 4-4.

Loss of cohesion, small dark pyknotic (see figure 6 in chapter 4-4) or wavy nuclei (see figure 4 in chapter 4-12), or “pseudo-vasculitis” (4) appearance of the smooth muscle cells (polylobulated degenerated nuclei)

See figure 4 in chapter 4-4 and figure 4 in chapter 5-4

Stem villous vascular obliteration with intravascular karyorrhexis (see chapter 8-4 figure 4a)

Stem villous vascular obliteration including early pattern with intraluminal recanalized-like vascular changes (see figure 4b in chapter 8-4)

Appendix I References

Genest

Singer

Estimating the time of death in stillborn fetuses: III. External fetal examination; a study of 86 stillborns

Obstet Gynecol

1992

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593

600

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Jacques

Qureshi

Johnson

Alkatib

Kmak

Estimation of time of fetal death in the second trimester by placental histopathological examination

Pediatr Dev Pathol

2003

;

226

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PubMed

Genest

Estimating the time of death in stillborn fetuses: II. Histologic evaluation of the placenta; a study of 71 stillborns

Obstet Gynecol

1992

;

585

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PubMed

Genest

Granter

Pinkus

Umbilical cord ‘pseudo-vasculitis' following second trimester fetal death: a clinicopathological and immunohistochemical study of 13 cases

Histopathology

1997

;

563

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PubMed

APPENDIX J: DIAGNOSTIC GROUPS

Fetal anomalies/aneuploidy
- Single umbilical artery
- Supranummery umbilical vein
- Short or long umbilical cord
- Thick umbilical cord
- Hypercoiled umbilical cord
- Umbilical artery aneurysm
- Villous edema
- Small placenta by weight
- Chronic chorioamnionitis
- Massive subchorionic thrombohematoma
- Delayed villous maturation
- Placental mesenchymal dysplasia
- Fetal vascular malperfusion
- Infectious villitis: syndromes
- Chorangiosis
- Chorangiomatosis
- Chronic histiocytic intervillositis
- Features of maternal glucose intolerance (diabetes mellitus)
- Hydrops placentalis
- Those as per specific anomalies as:
  - Vacuolated amniocytes in gastroschisis
  - Umbilical cord cysts or pseudocysts as in patent urachus or patent vitelline duct
  - Persistent vitelline duct or vitelline cyst with intestinal anomalies
  - Umbilical cord ulceration with intestinal atresia
  - Circulating hematopoietic blast forms in Trisomy 21
Cholestasis of pregnancy (untreated) (1)
- Maternal vascular malperfusion (accelerated villous maturation, increased syncytial knots)
- Focally thickened amniotic basement membrane
Maternal coagulopathy
- Massive subchorial hematoma(s)
- Massive perivillous fibrin deposition/maternal floor infarct
Neonatal death
- Massive perivillous fibrin deposition/maternal floor infarct
- Chronic histiocytic intervillositis
- Features associated with neonatal encephalopathy
- Hydrops placentalis
- Infections - acute chorioamnionitis, infectious chronic villitis
- Features/complications of prematurity
- Meconium
- Oligohydramnios - see #7 below
- Polyhydramnios - see #8 below
- Anomalies - see #1 above
Macrosomia
- Features associated with maternal diabetes
- Polyhydramnios - see #8 below
- Hydrops placentalis
- Features associated with acute hypoxia
- Heavy placenta
- Long umbilical cord
- Placental mesenchymal dysplasia - Beckwith-Wiedemann syndrome
Maternal obesity
- Villitis of unknown etiology
- Long umbilical cord
- Velamentous insertion of the umbilical cord
- Thick umbilical cord
- Hypocoiled umbilical cord
- Delayed villous maturation
Oligohydramnios
- Amnion nodosum
- Circumvallation
- Thick meconium
- Diffuse chorioamniotic hemosiderosis
- Donor in twin-twin transfusion syndrome - monochorionic diamniotic placentation
- Velamentous insertion of the umbilical cord
- Hypocoiled or flat umbilical cord
- Single umbilical artery
- Chronic chorioamnionitis
- Chorion nodosum
- Maternal vascular malperfusion
- Fetal vascular malperfusion
- Massive perivillous fibrin deposition/maternal floor infarct
- Chronic histiocytic intervillositis
Polyhydramnios
- Chorangioma(s)
- Umbilical cord hemangioma
- Recipient in twin-twin transfusion syndrome - monochorionic diamniotic placentation
- Hydrops placentalis
- Velamentous insertion of the umbilical cord
- Single umbilical artery
Postpartum hemorrhage
- Basal plate myometrial fibers/placenta accreta spectrum
- Acute chorioamnionitis
- Short umbilical cord
- Placenta membranacea
- Features associated with maternal diabetes
- Disrupted placenta
Post-term delivery
- Meconium and meconium-associated myonecrosis
- Increased dystrophic calcifications
Precipitous delivery
- Acute abruption
- Acute chorioamnionitis
- Features associated with acute hypoxia
Recurrent pregnancy losses
- Chronic histiocytic intervillositis
- Massive perivillous fibrin deposition/maternal floor infarct
- Villitis of unknown etiology

Fetal anomalies/aneuploidy
- Single umbilical artery
- Supranummery umbilical vein
- Short or long umbilical cord
- Thick umbilical cord
- Hypercoiled umbilical cord
- Umbilical artery aneurysm
- Villous edema
- Small placenta by weight
- Chronic chorioamnionitis
- Massive subchorionic thrombohematoma
- Delayed villous maturation
- Placental mesenchymal dysplasia
- Fetal vascular malperfusion
- Infectious villitis: syndromes
- Chorangiosis
- Chorangiomatosis
- Chronic histiocytic intervillositis
- Features of maternal glucose intolerance (diabetes mellitus)
- Hydrops placentalis
- Those as per specific anomalies as:
  - Vacuolated amniocytes in gastroschisis
  - Umbilical cord cysts or pseudocysts as in patent urachus or patent vitelline duct
  - Persistent vitelline duct or vitelline cyst with intestinal anomalies
  - Umbilical cord ulceration with intestinal atresia
  - Circulating hematopoietic blast forms in Trisomy 21
Cholestasis of pregnancy (untreated) (1)
- Maternal vascular malperfusion (accelerated villous maturation, increased syncytial knots)
- Focally thickened amniotic basement membrane
Maternal coagulopathy
- Massive subchorial hematoma(s)
- Massive perivillous fibrin deposition/maternal floor infarct
Neonatal death
- Massive perivillous fibrin deposition/maternal floor infarct
- Chronic histiocytic intervillositis
- Features associated with neonatal encephalopathy
- Hydrops placentalis
- Infections - acute chorioamnionitis, infectious chronic villitis
- Features/complications of prematurity
- Meconium
- Oligohydramnios - see #7 below
- Polyhydramnios - see #8 below
- Anomalies - see #1 above
Macrosomia
- Features associated with maternal diabetes
- Polyhydramnios - see #8 below
- Hydrops placentalis
- Features associated with acute hypoxia
- Heavy placenta
- Long umbilical cord
- Placental mesenchymal dysplasia - Beckwith-Wiedemann syndrome
Maternal obesity
- Villitis of unknown etiology
- Long umbilical cord
- Velamentous insertion of the umbilical cord
- Thick umbilical cord
- Hypocoiled umbilical cord
- Delayed villous maturation
Oligohydramnios
- Amnion nodosum
- Circumvallation
- Thick meconium
- Diffuse chorioamniotic hemosiderosis
- Donor in twin-twin transfusion syndrome - monochorionic diamniotic placentation
- Velamentous insertion of the umbilical cord
- Hypocoiled or flat umbilical cord
- Single umbilical artery
- Chronic chorioamnionitis
- Chorion nodosum
- Maternal vascular malperfusion
- Fetal vascular malperfusion
- Massive perivillous fibrin deposition/maternal floor infarct
- Chronic histiocytic intervillositis
Polyhydramnios
- Chorangioma(s)
- Umbilical cord hemangioma
- Recipient in twin-twin transfusion syndrome - monochorionic diamniotic placentation
- Hydrops placentalis
- Velamentous insertion of the umbilical cord
- Single umbilical artery
Postpartum hemorrhage
- Basal plate myometrial fibers/placenta accreta spectrum
- Acute chorioamnionitis
- Short umbilical cord
- Placenta membranacea
- Features associated with maternal diabetes
- Disrupted placenta
Post-term delivery
- Meconium and meconium-associated myonecrosis
- Increased dystrophic calcifications
Precipitous delivery
- Acute abruption
- Acute chorioamnionitis
- Features associated with acute hypoxia
Recurrent pregnancy losses
- Chronic histiocytic intervillositis
- Massive perivillous fibrin deposition/maternal floor infarct
- Villitis of unknown etiology

Appendix J Reference

Geenes

Lim

Bowman

, et al.

A placental phenotype for intrahepatic cholestasis of pregnancy

Placenta

2011

;

1026

Google Scholar

PubMed

Appendices

APPENDIX A: PLACENTAL WEIGHT STANDARDS

Appendix A References

APPENDIX B: UMBILICAL CORD LENGTH STANDARDS

Appendix B References

APPENDIX C: UMBILICAL CORD DIAMETER STANDARDS

Appendix C References

APPENDIX D: UMBILICAL CORD COILING INDEX

Appendix D References

APPENDIX E: BIRTH WEIGHT/PLACENTAL WEIGHT RATIO STANDARDS

Appendix E References

APPENDIX F: REPORTING

Appendix F References

APPENDIX G: CRITICAL VALUES

APPENDIX H: PLACENTA GROSS DICTATION TEMPLATES AND EXAMPLES

APPENDIX I: PLACENTAL WEIGHT STANDARDS

Appendix I References

APPENDIX J: DIAGNOSTIC GROUPS

Appendix J Reference

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Appendices Free

APPENDIX A: PLACENTAL WEIGHT STANDARDS

Appendix A References

APPENDIX B: UMBILICAL CORD LENGTH STANDARDS

Appendix B References

APPENDIX C: UMBILICAL CORD DIAMETER STANDARDS

Appendix C References

APPENDIX D: UMBILICAL CORD COILING INDEX

Appendix D References

APPENDIX E: BIRTH WEIGHT/PLACENTAL WEIGHT RATIO STANDARDS

Appendix E References

APPENDIX F: REPORTING

Appendix F References

APPENDIX G: CRITICAL VALUES

APPENDIX H: PLACENTA GROSS DICTATION TEMPLATES AND EXAMPLES

APPENDIX I: PLACENTAL WEIGHT STANDARDS

Appendix I References

APPENDIX J: DIAGNOSTIC GROUPS

Appendix J Reference

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