Oral Presentation Women's Health Forum 2021

Longitudinal association between physical activity in pregnancy with maternal and infant outcomes: findings from the Australian Longitudinal Study of Women’s Health (#23)

Kassia Beetham 1 , Jemima Spathis 1 , Samantha Hoffmann 2 , Wendy Brown 3 , Vicki Clifton 4 , Gregore Mielke 3
  1. Australian Catholic University, Banyo, QLD, Australia
  2. School of Exercise and Nutrition Sciences, Deakin University, Geelong, VIC, Australia
  3. School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, QLD, Australia
  4. Mater Research Institute, Brisbane, QLD, Australia

Introduction Physiological variations in each trimester of pregnancy may warrant different exercise prescriptions in each stage of pregnancy. The aim of this study was to examine associations between different volumes of physical activity in each trimester and maternal and infant outcomes.

Methods The study involved 2,376 participants in the Australian Longitudinal Study on Women’s Health, who completed surveys when they were pregnant, between 2006 and 2012 (aged 28-39 years). Women reported being in either the first, second or third trimester of pregnancy. Women who reported their physical activity during pregnancy also completed a child data survey three years after the survey completed when pregnant, relating to outcomes associated with pregnancy and childbirth.  Physical activity during pregnancy was categorised as ‘none’ (0-<33.3 MET.min/week), ‘low’ (33.3-<500 MET.min/week), ‘moderate’ (500-<1000 MET.min/week) or ‘high’ (≥1000 MET.min/week). In the present study, meeting the physical activity guideline was defined as ≥500 MET.min/week.

Results Fewer than half the women met the guideline of ≥500 MET.min/week in the first trimester of pregnancy (39.1%). This proportion was lower in women who were in the second (36.6%) and third (31%) trimesters. Only 11.4% reported high volumes of physical activity in the third trimester. There were no associations between physical activity volume in any trimester and infant birth weight, prematurity, gestational diabetes, hypertension, or antenatal depression. However, any physical activity during pregnancy (compared with none), regardless of volume, was associated with reduced prevalence of antenatal anxiety reported in any trimester (p=0.035).

Conclusion The majority of women do not meet the guideline for moderate-vigorous physical activity during pregnancy, and the proportion who meet this guideline is lower in the second and third trimesters than in the first. The findings also indicate that different volumes of physical activity appear to be safe throughout pregnancy, as there were no associations with the measured adverse health outcomes.