One of out every 10 women aged 24 or younger continues to smoke after becoming pregnant, an Environment Ministry survey said Sunday.
The nationwide survey, conducted on some 33,000 pregnant women and their partners from 2011 to 2012, also said 63 percent of their partners smoke.
The findings are stoking concerns about the proliferation of tobacco-related health defects in babies, including low birth weight.
“It is cause for concern, based on the results, that babies’ health may be damaged by secondhand smoking after birth, too,” said Zentaro Yamagata, a University of Yamanashi professor involved in the study. “Pregnant women and those close to them need to refrain from smoking.”
It was the first large-scale study on smoking rates among couples preparing for childbirth, the ministry said.
Overall, 5 percent of pregnant women and 45 percent of their partners smoked during the early stages of pregnancy, the survey said.
The smoking rates, however, declined as ages increased, with 4 percent of women 40 or older, and 37 percent of their partners, continuing to smoke during pregnancy.