Neonatal outcomes in pregnancies after bariatric surgery: a retrospective multi-centric cohort study in three French referral centers

Objective: To analyze short-term neonatal outcomes in pregnancies after bariatric surgery according to procedure, to the body mass index (BMI) at the beginning of the pregnancy and to the interval from surgery to conception, using a retrospective multi-centric cohort study in three French tertiary perinatal care and bariatric centers. Methods: 94 neonates in 79 women were included. Frequencies of adverse neonatal events by procedure, laparoscopic adjustable gastric banding (LAGB, n = 63) or Roux-en-Y gastric bypass (RYGB, n = 31), BMI class (72 women with BMI >= 30 kg/m(2)) and interval between surgery and conception (43 deliveries of patients who conceived during the first postoperative year) were compared with chi(2) tests. For parametric continuous data, t-tests or analysis of variance were used; non-parametric distributions were compared with the Wilcoxon or Kruskal-Wallis tests. Results: Significantly lower mean birth weight (2993 g vs. 3253 g; p = 0.02) was observed after RYGB and the mean Z-score for birth weight was significantly closer to 0 in neonates of the LAGB group than in those of the RYGB group. However, no significant differences were noticed regarding small-for-gestational age (32.3% vs. 17.1%; p = 0.06), umbilical arterial blood pH < 7.0 (9.7% vs. 0%; p = 0.11), low Apgar scores, perinatal mortality, and NICU admission. Neonatal outcomes according to the interval from surgery to conception or to the BMI at the beginning of the pregnancy were not significantly different. Conclusions: The short-term neonatal outcomes are basically comparable in pregnancies after RYGB than after LAGB.