A prospective study of physical activity and fecundability in women with a history of pregnancy loss

Lindsey M Russo; Brian W Whitcomb; Sunni L Mumford; Marquis Hawkins; Rose G Radin; Karen C Schliep; Robert M Silver; Neil J Perkins; Keewan Kim; Ukpebo R Omosigho; Daniel L Kuhr; Tiffany L Holland; Lindsey A Sjaarda; Enrique F Schisterman

doi:10.1093/humrep/dey086

Lifestyle and Environment · Physical Activity

A prospective study of physical activity and fecundability in women with a history of pregnancy loss

Russo LM, Whitcomb BW, Mumford SL, Hawkins M, Radin RG, Schliep KC, Silver RM, Perkins NJ, Kim K, Omosigho UR, Kuhr DL, Holland TL, Sjaarda LA, Schisterman EF

Published July 2018 Human reproduction (Oxford, England), 33(7), 1291-1298

DOI 10.1093/humrep/dey086 PMID 29648647 PMC PMC6012250

RRM Academy Synopsis

Vigorous Exercise Linked to Higher Pregnancy Odds After Loss

In a secondary analysis of the EAGeR trial, women who exercised strenuously more than four hours a week had better odds of becoming pregnant, no matter their weight. Walking 10 minutes without a break was also tied to better odds, but only among heavier women. The analysis covered 1,214 women with prior pregnancy loss.

Key Findings

Heavier women (overweight or obese by BMI) who took a 10-minute walk without stopping had better pregnancy chances than heavier women who did not (adjusted FOR 1.82, 95% CI 1.19 to 2.77).
Women of normal weight or underweight showed no link between walking and chance of pregnancy (adjusted FOR 0.83, 95% CI 0.58 to 1.19); the walking-by-BMI interaction was significant (P=0.01).
Women who did vigorous exercise over 4 hours a week had better pregnancy odds than those who did none, no matter their BMI (adjusted FOR 1.69, 95% CI 1.24 to 2.31).
No link appeared between pregnancy chances and time spent sitting, activity levels in between light and vigorous, or the summary IPAQ exercise score, overall or split by weight category.
Of the 1,214 enrolled women, each with one or two earlier pregnancy losses, 797 (65.7%) had a positive pregnancy test, and 1,128 were analyzed in the pregnancy-chance models.

Interpretation

This secondary analysis draws on the EAGeR trial, which enrolled 1,214 women with one or two prior pregnancy losses and followed them through up to six cycles of trying to conceive. The pattern split by body size: brisk walking mattered most for women carrying more weight, while vigorous exercise mattered for every weight group. The authors note that diet and weight change were not tracked over the study. The findings support larger studies of exercise and pregnancy chances after a loss.

RRM Context

Restorative reproductive medicine weighs these same factors in a workup. A clinician charts a woman's cycle alongside her weight and activity level. The combination shapes a plan specific to each woman.

Our editorial summary of this paper, not the article's abstract.

Abstract

Study Question

Is physical activity (PA) associated with fecundability in women with a history of prior pregnancy loss?

Summary Answer

Higher fecundability was related to walking among overweight/obese women and to vigorous PA in women overall.

What Is Known Already

PA may influence fecundability through altered endocrine function. Studies evaluating this association have primarily utilized Internet-based recruitment and self-report for pregnancy assessment and have yielded conflicting results.

Study Design, Size, Duration

This is 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.

Participants/Materials, Setting, Methods

Healthy women (n = 1214), aged 18-40 and with 1-2 prior pregnancy losses, were recruited from four US medical centers. Participants were followed for up to six menstrual cycles while attempting pregnancy and through pregnancy for those who became pregnant. Time to hCG detected pregnancy was assessed using discrete-time Cox proportional hazard models to estimate fecundability odds ratios (FOR) adjusted for covariates, accounting for left truncation and right censoring.

Main Results and the Role of Chance

The association of walking with fecundability varied significantly by BMI (P-interaction = 0.01). Among overweight/obese women, walking ≥10 min at a time was related to improved fecundability (FOR = 1.82, 95% CI: 1.19, 2.77). In adjusted models, women reporting >4 h/wk of vigorous activity had significantly higher fecundability (FOR = 1.69, 95% CI: 1.24, 2.31) compared to no vigorous activity. Associations of vigorous activity with fecundability were not significantly different by BMI (P-interaction = 0.9). Moderate activity, sitting, and International Physical Activity Questionnaire (IPAQ) categories were not associated with fecundability overall or in BMI-stratified analyses.

Limitations, Reasons for Caution

Some misclassification of PA levels as determined by the short form of the IPAQ is likely to have occurred, and may have led to non-differential misclassification of exposure in our study. Information on diet and change in BMI was not collected and may have contributed to some residual confounding in our results. The generalizability of our results may be limited as our population consisted of women with a history of one or two pregnancy losses.

Wider Implications of the Findings

These findings provide positive evidence for the benefits of PA in women attempting pregnancy, especially for walking among those with higher BMI. Further study is necessary to clarify possible mechanisms through which walking and vigorous activity might affect time-to-pregnancy.

Study Funding/Competing Interests

This work was funded by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The authors report no conflicts of interest in this work.

Trial Registration

#NCT00467363.

Topics

Lifestyle and Environment Physical Activity Exercise and Ovulation

Lifestyle and Environment › Physical Activity › Exercise and Ovulation

Lindsey M Russo, Brian W Whitcomb, Sunni L Mumford, Marquis Hawkins, Rose G Radin, Karen C Schliep, Robert M Silver, Neil J Perkins, Keewan Kim, Ukpebo R Omosigho, Daniel L Kuhr, Tiffany L Holland, Lindsey A Sjaarda, Enrique F Schisterman

L Russo, B Whitcomb, S Mumford, M Hawkins, R Radin, K Schliep, Bob Silver, Rob Silver, Bobby Silver, R Silver, N Perkins, K Kim, U Omosigho, Dan Kuhr, Danny Kuhr, D Kuhr, T Holland, L Sjaarda, E Schisterman

PMID 29648647 29648647 DOI 10.1093/humrep/dey086 10.1093/humrep/dey086 Russo et al. 2018, Russo 2018

A prospective study of physical activity and fecundability in women with a history of pregnancy loss

Vigorous Exercise Linked to Higher Pregnancy Odds After Loss

Key Findings

Interpretation

RRM Context

Abstract

Topics

By this author

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