Reduced versus nonreduced twin pregnancies: Obstetric performance in a cohort of interventional conceptions

Objective: To describe the obstetric performance of a selected population of twin pregnancies, comparing reduced vs. nonreduced twin pregnancies after the successful completion of the 12th week. Design: Prospective cohort study. Setting: Outpatient fertility center. Patient(s): A cohort of 464 twin pregnancies including both ovulation induction and assisted reproductive technology pregnancies. Intervention(s): Fetal reduction. Main Outcome Measure(s): Pregnancy outcome and prematurity rate. Result(s): The study group included a cohort of 464 twin pregnancies in a single outpatient fertility center: 70 cases of twin pregnancies after a reduction procedure (15.1%) and 394 cases of nonreduced twins (84.9%). Of the nonreduced twin pregnancies, 8.6% went through an abortion, as compared with 4.3% in the reduced group. Mean age at delivery was also comparable between the two groups (35.8 weeks in the reduced group, 35.6 weeks in the nonreduced group), as was the rate of severe prematurity (3.3% in the nonreduced group, 2.9% in the reduced group). Conclusion(s): Our work supports a lack of causative relationship between fetal reduction and pregnancy endpoint.