The influence of obesity on perinatal outcomes in pregnancies achieved with assisted reproductive technology: A population-based retrospective cohort study

Objective: To determine the influence of obesity on neonatal outcomes of pregnancies resulting from assisted reproductive technology. Methods: Population-based retrospective cohort study of all non-anomalous, live births in Ohio from 2007 to 2011, comparing differences in the frequency of adverse neonatal outcomes of women who conceived with assisted reproductive technology versus spontaneously conceived pregnancies and stratified by obesity status. Primary outcome was a composite of neonatal morbidities defined as ≥1 of the following: neonatal death, Apgar score of 7 at 5 min, assisted ventilation, neonatal intensive care unit admission, or transport to a tertiary care facility. Results: Rates of adverse neonatal outcomes were significantly higher for assisted reproductive technology pregnancies than spontaneously conceived neonates; non-obese 25% versus 8% and obese 27% versus 10%, p 0.001. Assisted reproductive technology was associated with a similar increased risk for adverse outcomes in both obese (adjusted odds ratio (aOR): 1.33, 95% confidence interval (CI): 1.11–1.59) and non-obese women (aOR: 1.34, 95% CI: 1.18–1.51) even after adjustment for coexisting risk factors. This increased risk was driven by higher preterm births in assisted reproductive technology pregnancies; obese (aOR: 1.06, 95% CI: 0.86–1.31) and non-obese (aOR: 1.15, 95% CI: 1.00–1.32). Discussion: Assisted reproductive technology is associated with a higher risk of adverse neonatal outcomes. Obesity does not appear to adversely modify perinatal risks associated with assisted reproductive technology.