Exercise in pregnancy: 1-year and 7-year follow-ups of mothers and offspring after a randomized controlled trial

Abstract

There are limited data on long-term outcomes of mothers or their offspring following exercise interventions during pregnancy. We assessed long-term effects of an exercise intervention (home-based stationary cycling) between 20-36 weeks of gestation on anthropometry and body composition in mothers and offspring after 1 and 7 years. 84 women were randomised to intervention or usual activity, with follow-up data available for 61 mother-child pairs (38 exercisers) at 1 year and 57 (33 exercisers) at 7 years. At 1 year, there were no observed differences in measured outcomes between mothers and offspring in the two groups. At the 7-year follow-up, mothers were mostly similar, except that exercisers had lower systolic blood pressure (-6.2 mmHg; p = 0.049). However, offspring of mothers who exercised during pregnancy had increased total body fat (+3.2%; p = 0.034) and greater abdominal (+4.1% android fat; p = 0.040) and gynoid (+3.5% gynoid fat; p = 0.042) adiposity compared with controls. Exercise interventions beginning during pregnancy may be beneficial to long-term maternal health. However, the initiation of exercise during pregnancy amongst sedentary mothers may be associated with adverse effects in the offspring during childhood. Larger follow-up studies are required to investigate long-term effects of exercise in pregnancy.

Figure 1

Summary of study recruitment and follow-up. Note that numbers at the 1-year follow-up represent the number of children assessed, as 18 mothers were not assessed (including 10 mothers who were pregnant again at the time of assessment).

Figure 2

Changes in anthropometry and body composition to follow-up at 7 years within control mothers (n = 24) and those who exercised in pregnancy (n = 33). Weight and body mass index (BMI) differences relate to pre-pregnancy values, while body composition changes are compared to measurements taken 2 weeks after delivery. Outliers have been determined using Tukey’s method, with inner fences equal to [Q1 – (1.5 * IQR)], where Q1 is quartile 1 and IQR is the interquartile range.

Figure 3

Differences in anthropometry and body composition to follow-up at 7 years within control mothers (black) and those who exercised in pregnancy (grey). Weight and body mass index (BMI) differences relate to pre-pregnancy values, while body composition changes are compared to measurements taken 2 weeks after delivery. Data are expressed as the mean change from baseline (Δ) and standard error, adjusted for BMI at baseline, current age, and number of pregnancies since the trial. *p < 0.05, **p < 0.01, and ***p < 0.001 vs baseline. There were no statistically significant differences between groups.