Is There a Cumulative Effect for Congenital Heart Defects in Monochorionic Twins after Assisted Reproduction? - A Retrospective Analysis at a Tertiary Referral Center.

This is the largest cohort study to date comparing maternal, chorionicity and neonatal complications between MC twin pregnancies after ART and after SC. Hypothyroidism was the only maternal condition occurring more frequently in pregnancies conceived after ART. There were no significant differences in chorionicity complications, in contrast to previously reported studies. While MC twins and ART pregnancies per se are known to be at risk for congenital heart defects, there seems to be a cumulative effect in MC pregnancies conceived after ART.