Abnormal placental perfusion and the risk of stillbirth: a hospital-based retrospective cohort study

Table 4 Estimated size of the effect of placental perfusion insufficiency on the risk of unexplained stillbirth stratified by sex (%)^a

Sex	Direct factor ^b	Total effect			The effect of PE			The effect of placental perfusion insufficiency
		Coef.	Standard Error	P value	Coef.	Standard Error	P value	Coef.	Standard Error	P value	Size of the total effect (%)
Male	APP	1.45	0.54	0.008	0.08	0.09	0.42	1.37	0.56	0.015	94.5
	PE	1.11	0.60	0.062	0.87	0.61	0.15	0.24	0.11	0.038	21.6
	Combined	2.56						1.61			62.9
Female	APP	1.83	0.54	0.001	0.15	0.10	0.12	1.68	0.59	0.004	91.8
	PE	1.60	0.52	0.002	1.28	0.55	0.02	0.31	0.12	0.008	19.4
	Combined	3.43						1.99			58.0
Total	APP	1.68	0.36	< 0.001	0.12	0.07	0.10	1.56	0.37	< 0.001	92.9
	PE	1.44	0.43	0.001	1.16	0.44	0.009	0.28	0.07	< 0.001	19.4
	Combined	3.12						1.84			59.0

^a Adjusted for maternal age at delivery (< 25, 25–34, or ≥ 35), residence (local or nonlocal), parity (nulliparous or pluriparous), gestational diabetes mellitus (yes or no), assisted conception (yes or no), preeclampsia (yes or no) and sex (male or female) in total. Sex was not included in the models of the stratification analyses
^b Direct factor refers to the factor associated with the risk of disease; indirect factor refers to the factor that may be involved in the aetiological chain of the direct factor and the occurrence of disease and that plays a role in the risk of disease

ISSN: 1471-2393