Timing of pregnancy after gastric bypass-a national register-based cohort study.

BACKGROUND: Current recommendations suggest postponing pregnancy by at least 1 year after gastric bypass. During the first postoperative year, women are in a catabolic phase with a rapid weight loss which may increase the risk of adverse pregnancy and neonatal outcomes. This study tested the hypothesis that the risk of adverse pregnancy and neonatal outcomes is increased in women who conceive during the first year after gastric bypass surgery.
METHODS: This is a national register-based cohort study covering all Danish deliveries during 2004-2010 in women with prior Roux-en-Y gastric bypass surgery. Only the first postoperative birth was included. The risk of adverse pregnancy and neonatal outcomes was compared between women who conceived within the first postoperative year and women who conceived later. Data were extracted from the Danish National Patient Registry and The Danish Medical Birth Register.
RESULTS: Of 286 women who had a singleton delivery after Roux-en-Y gastric bypass surgery, 158 women conceived within the first year and 128 later. There was no statistically significant difference (p > 0.05) between the two groups regarding neonatal birth weight, gestational age, risk of preeclampsia, gestational diabetes mellitus, labor induction, cesarean section, postpartum hemorrhage (>500 ml), preterm birth (before 37 weeks), small for gestational age, large for gestational age, or Apgar score (5 min ) below 7, or in the need of neonatal intensive care.
CONCLUSIONS: This study showed no evidence to support a recommendation to delay pregnancy until after the first postoperative year. At present, the optimal time for pregnancy after gastric bypass is unknown.