Chorionic-based intrahepatic cholestasis in pregnancy on perinatal outcome in twin pregnancies

This study investigates the impact of twin intrahepatic cholestasis in pregnancy (ICP) in different chorionicity scenarios on pregnancy outcome and risk factors. This retrospective study was designed to investigate the association between ICP and pregnancy outcomes and associated risk factors. Logistic regression analysis was used to verify the correlation between ICP and pregnancy outcome and the associated risk factors with the risk of ICP. Pregnant women with ICP had less gestational weight gain (16.19 ± 5.28 vs 17.78 ± 7.19, P = .018), a smaller number of deliveries (16.26% vs 26.40%, P = .016), and less spontaneous pregnancy (50.41% vs 61.73%, P = .019). The mean birth weight of pregnant women without ICP was lower (2328.07 ± 461.82 vs 2404.70 ± 504.58, P = .023), and the prepregnancy hepatitis B virus (HBV) antigen carrying rate was lower (12.20% vs 6.16%, P = .021). Pregnancy weight gain (0.95 (0.92, 0.99) P = .009) and the number of weeks in labor (0.88 (0.81, 0.96) P = .003) were negatively associated with the risk of ICP. Assisted reproductive technology use (1.38 (0.70, 1.79) P = .635) and HBV carrier before pregnancy (2.51 (1.42, 4.48) P = .002) were positively associated with ICP risk. In monochorionic twins, those with ICP were more likely to have abnormal amniotic fluid (15.79% vs 2.16%, P = .012), while those without ICP were less likely to have abnormal amniotic fluid (0.90 (0.83, 0.97) P = .004). In double chorion twins, the incidence of preterm birth was higher in women with ICP (40.00% vs 24.14, P = .002), and the risk of preterm birth was reduced in women without ICP (0.87 (0.79, 0.96) P = .005). In terms of neonatal outcomes, women with ICP were more likely to have a stillbirth (5.26% vs 0.48% P = .037), and stillbirth was less likely to occur without ICP (0.95 (0.92, 0.98) P = .002). Our study illustrates that twin pregnancies with maternal comorbid ICP have lower birth weight, degree of weight gain during pregnancy and prepregnancy HBV carriage is strongly associated with the development of ICP. ICP contributes to adverse perinatal outcomes such as stillbirth, preterm labor, and differentiates between different chorionic twin pregnancy outcomes. The risk of ICP is differently affected by the degree of weight gain during pregnancy, gestational week of delivery, assisted reproductive technology, and prepregnancy HBV carriage.