Pregnancy and leisure time physical activity

ABSTRACT
Aims: To examine associations between leisure time physical activity before and during pregnancy and preterm delivery, birth weight, and pre-eclampsia and to describe levels of physical activity prior to and during pregnancy. Furthermore to elucidate women’s experiences and views of leisure time physical activity during pregnancy in a qualitative study. Methods: Data sources were: the Aarhus Birth Cohort (1989-1991), the Smoke-free Newborn Study (1996-1998), and the Danish Dystocia Study (2004-2005) including from 2750 to 5750 pregnant women in each study population. Questionnaires provided information about leisure time physical activity (sedentary, light, moderate-to-heavy and competitive sports) and sports. Findings: Pregnant women engaged in moderate-to-heavy leisure time physical activity during pregnancy had a 66% significantly reduced risk of preterm delivery (adjusted OR=0.34, 95% CI:0.14-0.85), while women with light leisure time physical activity had an unchanged risk compared to sedentary women. Practicing more than 1 type of sports was associated with a 91% significantly reduced risk of preterm delivery. Women performing sports 1-2 hours, or 3 hours or more weekly during pregnancy delivered infants with similar birth weight, and had similar risk of infants with low (<2500g) or high birth weight (>4500g) as sedentary women. Similar findings were found when leisure time physical activity was studied. Women engaged in leisure time physical activities prior to pregnancy had the same risk of pre-eclampsia as sedentary women. From prior to pregnancy to the third trimester women’s level of leisure time physical activity decreased. Women with the highest level of leisure time physical activity before pregnancy remained the most physically active in leisure time during pregnancy. The qualitative study indicated that pregnant women desired to continue to be physically active in leisure time. Pregnancy-related discomforts/complications, a growing body and senses of insecurity with physically activity during pregnancy were barriers to maintain previous levels of physical activity. The women experienced that it was most often possible to overcome these barriers and continue to be active, and felt enjoyment and physical well-being from doing this.
Conclusions: This thesis contributes new knowledge on the subject by demonstrating that pregnant women performing leisure time physical activity with the highest intensity had the lowest risk of preterm delivery. No associations between leisure time physical activity and offspring birth weight or risk of pre-eclampsia were found. It is a new dimension that pregnant women described their experiences in overcoming barriers in order to continue to be psychically active.
The overall conclusion is that, that performing sports or higher level of leisure time physical activity prior to pregnancy or during pregnancy is not associated with disadvantages; rather there are some psychological and physical benefits for the mother and her offspring.