Table 3.

Prevalence and Odds Ratios of Small for Gestational Age (SGA) Infant and Fetal-Placental Weight Ratio for Each Placental Pathology Group (n = 19,027).

Group Name and Description	Group Number	Included Phenotypes	N	Percent	SGAa			Fetal-Placental Weight Ratiob
					Percent SGA	OR	95% CI	Mean	β (95% CI)
Multiple high-grade pathologies (C, F, M)	1		771	4.1%	39.0%	14.08	10.49, 18.90	7.77	0.86 (0.75, 0.96)
All three high-grade pathologies (triple threat)	1a	CFM, aCFM, ACFM	34		38.2%
High-grade fetal AND maternal vascular pathology	1b	FM, cFM, aFM, acFM, AFM, AcFM	113		48.7%
High-grade maternal vascular pathology AND high-grade chronic inflammation	1c	CM, CfM, aCM, aCfM, ACM, ACfM	536		38.2%
High-grade fetal vascular pathology AND high-grade chronic inflammation	1d	CF, CFm, aCF, aCFm	88		31.8%
High-grade acute inflammation AND high-grade fetal vascular pathology (with or without chronic inflammation and/or low-grade maternal vascular pathology)	2	AF, AFm, AcF, AcFm, ACF, ACFm	122	0.6%	11.5%	2.85	1.54, 5.26	7.05	0.01 (−0.22, 0.23)
High-grade fetal vascular pathology
With or without low-grade acute inflammation	3a	F, aF	160	0.8%	14.4%	3.69	2.21, 6.15	6.97	−0.10 (−0.30, 0.10)
WITH low-grade chronic inflammation AND/OR low-grade maternal vascular pathology (with or without low-grade acute inflammation)	3b	cF, Fm, cFm, acF, aFm, acFm	171	0.9%	29.8%	9.34	6.16, 14.17	7.22	0.24 (0.05, 0.44)
High-grade chronic inflammation
With or without low-grade fetal vascular pathology	4a	C, Cf	654	3.4%	13.5%	3.42	2.43, 4.81	7.22	0.33 (0.22, 0.45)
WITH any acute inflammation (with or without low-grade fetal vascular pathology)	4b	aC, aCf, AC, ACf	719	3.8%	11.0%	2.71	1.92, 3.84	7.28	0.26 (0.15, 0.37)
WITH low-grade maternal vascular pathology (with or without low-grade fetal vascular pathology)	4c	Cm, Cfm	263	1.4%	27.0%	8.13	5.59, 11.82	7.50	0.54 (0.38, 0.70)
WITH low-grade maternal vascular pathology AND any acute inflammation	4d	aCm, aCfm, ACm, ACfm	276	1.5%	19.9%	5.47	3.70, 8.09	7.64	0.59 (0.43, 0.75)
High-grade maternal vascular pathology (with or without any acute inflammation and/or other low-grade pathology)	5	M, cM, fM, cfM, aM, acM, afM, acfM, AM, AcM, AfM, AcfM	2673	14.0%	30.1%	9.46	7.22, 12.38	8.03	0.95 (0.87, 1.03)
Low-grade fetal vascular pathology OR chronic inflammation
With or without low-grade acute inflammation	6a	c, f, ac, af	2574	13.5%	9.4%	2.29	1.72, 3.06	7.16	0.21 (0.13, 0.29)
WITH high-grade acute inflammation	6b	Ac, Af	917	4.8%	7.8%	1.87	1.32, 2.66	7.04	−0.01 (−0.11, 0.09)
Low-grade maternal vascular pathology OR any combination of low-grade chronic inflammation and fetal vascular malperfusion
Without acute inflammation	7a	m, cm, cf, fm, cfm	1680	8.8%	18.5%	4.97	3.74, 6.61	7.47	0.44 (0.36, 0.53)
WITH low-grade acute inflammation	7b	am, acm, acf, afm, acfm	1554	8.2%	18.7%	5.07	3.80, 6.75	7.52	0.50 (0.41, 0.58)
WITH high-grade acute inflammation	7c	Am, Acm, Acf, Afm, Acfm	924	4.9%	16.0%	4.19	3.07, 5.72	7.48	0.37 (0.27, 0.47)
Other significant pathology Acute inflammation alone	8		1455	7.6%	19.4%	5.29	3.96, 7.05	7.89	0.88 (0.79, 0.97)
High-grade acute inflammation	9a	A	1082	5.7%	4.3%	1.00	0.68, 1.47	6.91	−0.17 (−0.27, −0.08)
Low-grade acute inflammation	9b	a	1630	8.6%	4.9%	1.13	0.81, 1.60	6.95	−0.04 (−0.13, 0.04)
Histologically normal	10		1402	7.4%	4.3%	Reference		6.87	Reference

Abbreviations: SGA – small for gestational age, OR – odds ratio, CI – confidence interval, A – high-grade acute inflammation, a – low-grade acute inflammation, C – high-grade chronic inflammation, c – low-grade chronic inflammation, F – high-grade fetal vascular malperfusion, f – low-grade fetal vascular malperfusion, M – high-grade maternal vascular malperfusion, m – low-grade maternal vascular malperfusion.

^aOdds ratios from logistic regression (null value is 1).

^bParameter estimates (β) from linear regression (null value is 0); model adjusted for gestational age and infant sex (excludes 454 fragmented placentas).