Maternal and neonatal outcomes for pregnancies before and after gastric bypass surgery

Abstract

BACKGROUND Interaction between maternal obesity, intrauterine environment and adverse clinical outcomes of newborns has been described. METHODS Using statewide birth certificate data, this retrospective, matched-control cohort study compared paired birth weights and complications of infants born to women before and after Roux-en-Y gastric bypass surgery (RYGB) and to matched obese non-operated women in several different groups. Women who had given birth to a child before and after RYGB (group 1; n = 295 matches) and women with pregnancies after RYGB (group 2; n = 764 matches) were matched to non-operated women based on age, body mass index (BMI) prior to both pregnancy and RYGB, mother’s race, year of mother/s birth, date of infant births and birth order. In addition, birth weights of 13 143 live births before and/or after RYGB of their mothers (n = 5819) were compared (group 3). RESULTS Odds ratios (ORs) for having a large-for-gestational-age (LGA) neonate were significantly less after RYGB than for non-surgical mothers: ORs for groups 1 and 2 were 0.19 (0.08–0.38) and 0.33 (0.21–0.51), respectively. In contrast, ORs in all three groups for risk of having a small for gestational age (SGA) neonate were greater for RYGB mothers compared to non-surgical mothers (ORs were 2.16 (1.00–5.04); 2.16 (1.43–3.32); and 2.25 (1.89–2.69), respectively). Neonatal complications were not different for group 1 RYGB and non-surgical women for the first pregnancy following RYGB. Pregnancy-induced hypertension and gestational diabetes were significantly lower for the first pregnancy of mothers following RYGB compared to matched pregnancies of non-surgical mothers. CONCLUSION Women who had undergone RYGB not only had lower risk for having an LGA neonate compared to BMI-matched mothers, but also had significantly higher risk for delivering an SGA neonate following RYGB. RYGB women were less likely than non-operated women to have pregnancy-related hypertension and diabetes.

Maternal and fetal delivery outcomes in pregnancies following bariatric surgery: a meta-analysis of the literature

“…The 6 studies included in this section found either no difference or an increased risk of SGA neonates among bariatric surgery patients [13,15,[19][20][21]23] while our data suggests an increased risk of SGA among the bariatric surgery woman as compared to the controls. However, this is potentially due to the same reasons as listed above for IUGR.…”

“…While there were a few select papers that showed no difference, the majority of the studies reviewed showed a significant decrease in the rates of both LGA and macrosomic neonates in the bariatric surgery patient. Women who gain less weight during the pregnancy, on average, have a decreased chance of delivering a LGA or macrosomic neonate [15] . Our analysis found there was a decreased incidence of both LGA and macrosomia in the bariatric surgical women who are obese, as compared to the obese controls.…”

Assessment of glucose regulation in pregnancy after gastric bypass surgery

“…Previous retrospective reports and register studies have addressed pregnancy complications and pregnancy outcomes following gastric bypass and have demonstrated beneficial effects such as reduced incidence of pre-existing and gestational diabetes mellitus (GDM) [8,9], possibly contributing to a lower prevalence of large for gestational age (LGA) offspring [10][11][12]. However, a marked increase in the prevalence of small for gestational age (SGA) neonates, along with a small increase in the rates of stillbirths or neonatal deaths, indicates a higher risk for perinatal morbidity and mortality [13,14].…”

Pregnancy after bariatric surgery: improving outcomes for mother and child

“…In addition, weight gain during pregnancy was found to positively correlate with the newborn’s body weight 54. This influence of maternal weight on neonatal weight is important at birth time, but also, and probably most importantly, there is a great amount of scientific evidence supporting that it significantly influences intrauterine fetal development, portending an increased risk of overweight and obesity during adolescence and adulthood 55–57…”

“…They found that babies born after maternal BS had lower birth weight, lower gestational age, 3.3-times lower risk of LGA, and 2.3-times higher risk of SGA than infants born to matched women without BS. In addition, a recent retrospective, matched-control cohort study has compared birth weights of babies born to women with pregnancies before and after RYGB surgery 54. Interestingly, the authors communicated that women who had undergone RYGB had a significantly lower risk for having an LGA newborn, but also a significantly increased risk for delivering an SGA neonate, than nonoperated women closely matched by age and BMI before pregnancy 54…”