Perinatal outcomes following bariatric surgery between a first and second pregnancy: a population data linkage study.

<bold>Objectives: </bold>To describe the population of women having bariatric surgery and compare the pregnancy outcomes for women having bariatric surgery with a non-bariatric surgery population having a first and second pregnancy.<bold>Design: </bold>Population-based record linkage study.<bold>Setting: </bold>New South Wales (NSW), Australia.<bold>Population: </bold>All women aged 15-45 years with a hospital record in NSW (2002-2014) and all women giving birth in NSW (1994-2015; n = 1 606 737 women).<bold>Methods: </bold>Pregnancy and birth outcomes were compared between first and second pregnancies using repeated-measures logistic regression and paired Student's t-tests. Bariatric and non-bariatric groups were also compared.<bold>Main Outcome Measures: </bold>Maternal diabetes, preterm birth (<37 weeks of gestation) and large for gestational age.<bold>Results: </bold>There was a 13-fold increase in hospitalisations for primary bariatric surgery during 2002-2014. Compared with the general birthing population, women who had bariatric surgery experienced higher rates of hypertension, diabetes, and preterm birth. Among women who had bariatric surgery between a first and second pregnancy, there were reduced rates of hypertension (OR 0.39, 95% CI 0.29-0.53), spontaneous preterm birth (OR 0.37, 95% CI 0.16-0.86), infants that were large for gestational age (OR 0.63, 95% CI 0.44-0.88), and the admission of infants to a special care nursery or neonatal intensive care (OR 0.64, 95% CI 0.46-0.90) in the second pregnancy. Rates for small-for-gestational age and gestational diabetes following surgery were 8.3 and 11.4%, respectively CONCLUSIONS: Bariatric surgery between a first and second pregnancy was associated with reductions in obesity-related adverse pregnancy outcomes. Bariatric surgery performed for the management of obesity in accordance with current clinical criteria is associated with improved pregnancy outcomes in a subsequent pregnancy.<bold>Tweetable Abstract: </bold>Bariatric surgery for obesity may improve pregnancy and birth outcomes in a subsequent pregnancy. [ABSTRACT FROM AUTHOR]