The influence of ovulation induction and assisted conception on maternal and perinatal outcomes of twin pregnancies.

OBJECTIVE To compare obstetrical and neonatal outcomes of twin pregnancies conceived via assisted reproductive technology (ART) with those of naturally conceived ones and to investigate the influence of the ART procedure type on these parameters. PATIENTS AND METHODS This observational study included 450 ART and 647 spontaneous twin pregnancies delivered over 15 years at a single university-based hospital of Rome, Italy. Logistic and linear regression models adjusted for confounding factors were used to evaluate the effect of ART and the type of assisted conception (IVF/ICSI, ovulation induction ± intrauterine insemination, egg/embryo donation) on maternal and perinatal outcomes. RESULTS The mean gestational age was significantly lower in pregnancies conceived via ART. The occurrence rates of gestational diabetes, antenatal admission, prophylactic administration of corticosteroid, very preterm delivery and neonatal intensive care unit admission were higher in the ART group. Twin pregnancies achieved via egg/embryo donation had a lower risk of maternal thrombocytopenia and cervical incompetence and were at greater risk of receiving corticosteroid prophylaxis and patent ductus arteriosus than pregnancies obtained by IVF/ICSI. Conception by ovulation induction was associated with reduced risk of hyperemesis gravidarum and longer neonatal hospitalization compared to pregnancies obtained by IVF/ICSI. CONCLUSIONS Assisted conception was associated with adverse obstetrical outcomes and lower gestational age, but after adjustment for gestational age neonatal immediate outcomes were similar to those observed in the spontaneous group. There were no many important differences in the outcomes of twin pregnancies obtained by a different type of conception.