Researchers have released the results of the first-ever international study of the tobacco use habits of pregnant women. Investigators say the rates of smoking, use of smokeless tobacco and exposure to secondhand smoke during pregnancy are higher than expected in developing and middle income countries, and pose an emerging threat to the health of women and their children. VOA's Jessica Berman reports.

An international team of researchers, wanting to get a first glimpse at the magnitude of the problem of tobacco use and exposure in pregnancy, surveyed 8,000 pregnant women in five countries in Latin America, two countries in Africa and three countries in Asia.

Researchers, led by investigators at the U.S. National Institutes of Health, found that the highest levels of smoking were in Latin America, with 18 percent of pregnant women in Uruguay and 10 percent of women in Argentina lighting up.

Investigators found smokeless tobacco was popular among up to one-third of pregnant women in some parts of India.

The highest levels of secondhand smoke exposure were found in Pakistan, where nearly half of all pregnant women reported that both they and their children were regularly exposed to someone else's smoke.

In the Democratic Republic of the Congo, investigators say 40 percent of those surveyed said they had tried smokeless tobacco at lease once, while fourteen percent of pregnant women had tried cigarettes. In Zambia, seven percent of respondents said they had tried cigarettes.

Michele Bloch, who is with the National Cancer Institute's Tobacco Control Branch and the study's lead author, says the findings are unexpected because traditionally, tobacco use among women in developing countries has been almost non-existent.

She says the results of the study are also disturbing because they suggest conditions could become ripe for women who are casual users to become addicted to tobacco products.

"These are countries with high levels of tobacco use by men, general high levels of tobacco use by health professionals and, I mean, these are places where knowledge of the health hazards is generally very low," she said. "So, we think that the women's lack of use is more based on economic factors or especially cultural factors. And were these to change, we'd be looking at a very different and a very threatening situation for women and their children."

Women who smoke during pregnancy are more likely to go into labor prematurely and give birth to low weight babies. Experts say smoking in pregnancy can also cause sudden infant death syndrome after the baby is born.

Linda Wright is Scientific Director of the Global Network at National Institute of Child Health and Human Development, which coordinated the global research effort.

The good news, according to Wright, is other studies have shown that women in developing countries are receptive to programs to help them quit tobacco products.

"Women are very concerned about their fetuses and children, so that if you intervene early in pregnancy with a short counseling period - it can be as short as five to 15 minutes and then follow up with print material if they are literate or more advanced counseling - then women will stop," she said.

The study on tobacco use and secondhand smoke exposure during pregnancy is published in an early online edition of The American Journal of Public Health.