Table 2.

Regression analyses of pathology findings, comparing male and female twins born in C&W hospital (1493 pairs, n = 2986)

	Unadjusted (95% CI)	Adjusted (95% CI)
Chorionitis	1.34 (1.01–1.79)	1.38 (1.04–1.84)a
Anastomosis	1.59 (1.22–2.07)	1.63 (1.22–2.19)b
Unequal placenta sharing	1.5 (1.03–2.33)	1.72 (1.11–2.64)a
Composite of inflammation	1.27 (1.02–1.58)	1.30 (1.05–1.62)a
Composite placenta lesions	1.86 (1.03–3.35)	1.83 (1.02–3.31)a
Cord length	1.46 (0.48–2.44)	1.35 (0.39–2.30)c

Ref: Female; ^aAdjusted for chorionicity

BMI ≥ 30% and gestational age

^bAdjusted for chorionicity and gestational age

^cAdjusted for BMI ≥ 30% and gestational age

&Two individual twins with unknown sex were excluded

Unequal placental sharing was defined as 1 twin receiving blood from more than 60% of the placenta

Composite of inflammation: Chorioamnioitis, chorionic villi inflammation, chorionitis, membrane inflammation and other abnormalities of amnion and chorion

Composite placenta lesions: Placenta infarction, placenta abnormalities, chorangioma, hematoma and placenta morphological and functional anomalies