Clinical outcomes after assisted reproductive technology in twin pregnancies: chorionicity-based comparison.

The chorionicity-based evaluation of the perinatal risk in twin pregnancies after assisted reproductive technology (ART) is lacking. A retrospective review was performed of all twin pregnancies monitored prenatally and delivered at our hospital between 2010 and 2014. Chorionicity was diagnosed by ultrasound examination at first trimester and confirmed by postnatal pathology. Pregnancy and perinatal outcomes were prospectively recorded. Adjusted odds ratios (aOR) with 95% confidence intervals (CI) were calculated in a logistic regression model. A total of 1153 twin pregnancies were analyzed. The occurrence of preterm premature rupture of membranes (PPROM) was 3 times as frequent in monochorionic diamniotic (MCDA) twin pregnancies after ART as in those spontaneous counterparts (aOR 3.0; 95%CI 1.1-3.2). The prevalence of intrahepatic cholestasis of pregnancies (ICP) was significantly higher in dichorionic diamniotic (DCDA) twin pregnancies following ART compared to spontaneous DCDA pregnancies (aOR 3.3; 95%CI 1.3-5.6). Perinatal outcomes did not differ between two conception methods, either in MCDA or DCDA twin pregnancies. Based on differentiation of chorionicity, ART is associated with the increased risk of PPROM in MCDA twin pregnancies and with a higher rate of ICP in DCDA twin gestations. ART does not increase adversity of perinatal outcomes in twin pregnancies.