TUESDAY, April 23, 2024 (HealthDay News) -- Active military service appears to increase a woman’s risk of having a low birthweight baby, a new review finds.

Nearly two-thirds of studies (63%) conclude that women on active service could be at higher risk of having a baby with low birth weight, researchers reported April 22 in the journal BMJ Military Health.

However, there was no clear evidence of an increased risk of stillbirth or premature birth among military women.

“This review highlights a need for more female-specific research in armed forces, beyond the U.S. military setting, to inform military maternity pathways and policies in ways that safeguard mothers and their babies,” concluded the research team led by Dr. Kirsten Morris, with the London School of Hygiene & Tropical Medicine in the U.K.

Increasing evidence has shown that stress during pregnancy is associated with birth complications, such as preterm delivery and low birth weight, researchers said in background notes.

To assess the evidence, researchers pooled data from 21 studies involving more than 650,000 women in the U.S. military, all published between 1979 and 2023.

Four out of five studies that compared active personnel to a control group -- usually the wives of male soldiers -- indicated an increased risk of low birthweight for the newborns of female service members, researchers said.

The study shows the need for more research into the effects of military service on women, given that increasing numbers of women are joining the military and being deployed in combat units, researchers concluded in a journal news release.

More information

The U.S. Department of Defense has more on women’s health in the military.

SOURCE: BMJ, news release, April 22, 2024