The research findings add another perspective to the lifecourse literature of cardiovascular disease in women, according to the article that is published in the journal BMJ Open.
"The study provided a unique opportunity to evaluate risk factors prior to pregnancy for their association with risk of stillbirth delivery," says Grace Margrethe Egeland, senior researcher at the Norwegian Institute of Public Health.
Increased risk with vigorous physical activity
The study also found that regular light physical activity three or more times per week was associated with reduced stillbirth risk, while vigorous activity (indicated by shortness of breath and sweating) was associated with greater stillbirth risk.
The researchers linked data from Cohort of Norway (CONOR) and the Medical Birth Registry of Norway. They evaluated 13,497 births greater than 22 weeks gestation to 8,478 women. There were 54 stillbirths (4 per 1,000).
Few experience a stillbirth delivery
In developed countries, there are approximately 4 stillbirths per 1,000 pregnancies, i.e., a seldom outcome. Researchers emphasize that the low number of stillbirths in the study can lead to misleading results.
Need for more research
According to the researchers, there is a need for more research in this arena.
The Norwegian SIDS and Stillbirth Society provided financial support of the project.