• Posted October 14, 2024

Exercise in Pregnancy Might Lower Baby's Odds for Asthma Later

A child’s risk of asthma can be cut by nearly half if their mother regularly works out while expecting, a new study says.

Exercising three or more times a week while pregnant reduces a child’s risk of asthma by about 46%, researchers reported Oct. 9 in the journal Med.

This level of protection is akin to an expecting mother or father quitting smoking while she’s pregnant, thus reducing her exposure to cigarette smoke, researchers noted. 

The results jibe with earlier studies that showed newborns have stronger lung function if their mothers regularly exercised during pregnancy, researchers noted.

“This is the first time we are observing an association between maternal exercise and the development of asthma in the child,” said lead investigator Emma-Reetta Musakka, a doctoral student with the University of Eastern Finland.

For the study, researchers analyzed data on nearly 1,000 mother-child pairs in Finland.

The mothers were asked whether they’d exercised during pregnancy, and how often they worked out. The most common exercises were walking (34%), jogging (32%), strength training (29%) and group exercise classes or working out at home (22%).

Mothers whose kids developed asthma tended to work out fewer than three times a week, results showed.

The lower asthma risk associated with regular exercise held even after researchers accounted for other factors like a mom’s weight, stress or illness; family exercise habits and nutrition; and even dog ownership.

“Our findings strongly suggest that maternal exercise during pregnancy has an independent positive effect on the fetus and on the later health of the child,” Musakka said in a university news release.

The results open up a new way of protecting children from asthma prior to birth, said senior researcher Pirkka Kirjavainen with the University of Eastern Finland.

“Until today, avoidance of cigarette smoke during pregnancy has been among the only effective ways to reduce a child’s risk of asthma,” Kirjavainen said. “Thus, it is intriguing that moderate maternal exercise during pregnancy may have an equally strong protective effect on a child’s asthma risk as if one of the parents quits smoking.”

However, the study did not indicate that increasing exercise beyond three times a week would lower asthma risk even further, researchers noted.

“The findings are very promising in terms of asthma prevention. It is highly encouraging to see that by engaging in reasonable amounts of exercise, mothers can significantly influence not only their own health, but also the health of their child,” Kirjavainen said.

More information

The American College of Obstetricians and Gynecologists have more about exercise during pregnancy.

SOURCE: University of Eastern Finland, news release, Oct. 9, 2024