Impact of induced pregnancies in the obstetrical outcome of twin pregnancies.

Objective: To compare obstetric outcomes of induced twins with those spontaneously conceived.

Design: A prospective observational study was conducted in twin pregnancies delivered over 16 years.

Setting: A tertiary obstetric center with differentiated perinatal support.

Patient(s): A total of 180 induced twins and 698 spontaneously conceived were included.

Intervention(s): None.

Main Outcome Measure(s): Comparison of demographic factors, obstetrical complications, gestational age at delivery, mode of delivery, birth weight, and immediate newborn outcome.

Result(s): First-trimester bleeding was higher in the induced group (6.0% vs. 12.2%), as were gestational diabetes (4.4% vs. 8.3%) and discordant intrauterine growth (4.3% vs. 11.1%). Preterm premature rupture of membranes was less frequent (23.9% vs. 12.8%) as was preterm delivery ≤32 weeks (22.5% vs. 14.0%). Cesarean section rate was higher (50.6% vs. 63.9%). Other obstetrical complications, newborn data, and puerperal complications were not statistically different. Except for first-trimester bleeding (significantly associated with monochorionicity), these results were independent from chorionicity. Regarding the induced method (ovulation induction, IVF, or ICSI), IVF is a predictor for first-trimester bleeding and IVF or ICSI a predictor for cesarean section.

Conclusion(s): The higher rates found with induced twins of first-trimester bleeding, gestational diabetes, and discordant growth do not contribute to different neonatal immediate outcomes and do not contribute to higher rates of prematurity, low birth weight, or other major perinatal complications.