Women who smoke during pregnancy are 20 percent more likely to report pelvic pain than nonsmokers, Reuters reported June 18.

A study of 5,000 women found that reports of pelvic pain were higher even among women who quit smoking during the first trimester of pregnancy. Up to one in three pregnant women may experience pelvic pain, which can impede mobility.

Researchers said that the study doesn’t necessarily mean smoking causes the pain, but their is an association, and reduction in pelvic pain could be an added benefit of quitting smoking for pregnant women. Smoking could reduce blood flow to pelvic tissue, researchers speculated.

The findings were published online in the journal BJOG: An International Journal of Obstetrics and Gynaecology.