Body mass index, physical activity and fecundability in a North American preconception cohort study
McKinnon, CJ., Hatch, EE., Rothman, K., Mikkelsen, EM., Wesselink, AK., Hahn, KA., & Wise, LA. (2016). Body mass index, physical activity and fecundability in a North American preconception cohort study. Fertility and Sterility, 106(2), 451-459. https://doi.org/10.1016/j.fertnstert.2016.04.011
OBJECTIVE: To evaluate the association between adiposity, physical activity (PA), and fecundability. DESIGN: Prospective cohort study. SETTING: Not applicable. PATIENT(S): A total of 2,062 female pregnancy planners from the United States and Canada who were enrolled during the preconception period. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Self-reported pregnancy. Fecundability ratios (FRs) and 95% confidence intervals (CIs) were estimated using proportional probabilities models that adjusted for potential confounders. RESULT(S): Relative to body mass index (BMI) 18.5-24 kg/m2, FRs for BMI /=45 kg/m2 were 1.05 (95% CI 0.76-1.46), 1.01 (95% CI 0.89-1.15), 0.98 (95% CI 0.82-1.18), 0.78 (95% CI 0.60-1.02), 0.61 (95% CI 0.42-0.88), and 0.42 (95% CI 0.23-0.76), respectively. Reduced fecundability was observed among women with the largest waist-to-hip ratios (>/=0.85 vs. /=36 vs. /=90 vs. /=5 vs. /=25 kg/m2), fecundability was 27% higher for vigorous PA of >/=5 versus
