Russo LM, et al. - Researchers sought to assess if physical activity (PA) is associated with fecundability in women with a history of prior pregnancy loss. They noted a higher fecundability in relation to walking among overweight/obese women and to vigorous PA in women overall.

Methods

• Researchers performed a secondary analysis of the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial (2007–2011), a multisite, randomized controlled trial of preconception-initiated low-dose aspirin.
• From four US medical centers, they recruited healthy women (n = 1214), aged 18–40 and with 1–2 prior pregnancy losses.
• They followed the participants for up to six menstrual cycles while attempting pregnancy and through pregnancy for those who became pregnant.
• Using discrete-time Cox proportional hazard models, time to hCG detected pregnancy was assessed to determine fecundability odds ratios (FOR) adjusted for covariates, accounting for left truncation and right censoring.

Results

• Significant variation in association between walking and fecundability was noted by BMI (P-interaction = 0.01).
• Walking ≥10 min at a time was related to improved fecundability (FOR = 1.82, 95% CI: 1.19, 2.77) among overweight/obese women.
• Women reporting >4 h/wk of vigorous activity showed significantly higher fecundability (FOR = 1.69, 95% CI: 1.24, 2.31) compared to no vigorous activity in adjusted models.
• No significant differences in associations of vigorous activity with fecundability were observed in relation to BMI (P-interaction = 0.9).
• In this study, moderate activity, sitting, and International Physical Activity Questionnaire (IPAQ) categories were not found to be associated with fecundability overall or in BMI-stratified analyses.