Second-trimester multifetal pregnancy reduction facilitates prenatal diagnosis before the procedure.

Objective: To evaluate the pregnancy outcome of selective second-trimester multifetal pregnancy reduction (MFPR) compared to first-trimester MFPR.

Design: Cohort analysis.

Setting: In Vitro Fertilization Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.

Patient(s): The study groups comprised 38 and 70 patients who underwent selective second-trimester MFPR (group 1) and first-trimester MFPR (group 2) at mean gestational ages of 19.7 +/- 3.3 weeks and 11.7 +/- 0.7 weeks, respectively.

Intervention(s): Ultrasonographically guided intracardiac injection of potassium chloride (KCl) solution.

Main Outcome Measure(s): Pregnancy outcome and obstetric complications.

Result(s): No statistically significant difference was found between group 1 and group 2 regarding mean gestational age at delivery (35.4 +/- 3.4 weeks and 35.9 +/- 3.1 weeks, respectively); mean birth weight (2,318.9 +/- 565.7 g and 2, 138.1 +/- 529.4 g); and the incidence of obstetric complications. These complications included pregnancy loss (5.2% and 15.7%), pregnancy-induced hypertension (0 and 10%), discordancy (12% and 18. 4%), intrauterine growth restriction (0 and 40%), and gestational diabetes (0% and 6%). However, the rate of all pregnancy complications was lower among second-trimester MFPR patients.

Conclusion(s): Selective second-trimester MFPR is associated with favorable perinatal outcome and may facilitate detection of structural and chromosomal anomalies before the procedure and selective reduction of the affected fetus.