What stress may do to an unborn baby

Pregnant women are advised to create a hospitable environment for their developing baby by eating right, taking prenatal vitamins and abstaining from alcohol.

Some doctors say stress reduction — or help coping with extreme circumstances — should be added to the list.

A new study published in the American Journal of Obstetrics and Gynecology finds that stressful circumstances early in pregnancy can lead to underweight babies or premature births. Chinese researchers studied 1,800 pregnant women and surveyed them on their emotional health and traumatic events such as death, divorce and job loss.

They found premature birth was more than twice as likely if severely stressful events occurred during the first and second trimesters, but not the third. Low birth weight was nearly three times more likely if stress happened during the first trimester.

Stress during pregnancy causes higher levels of cortisol and adrenaline in the fetus' bloodstream. After 9/11, pregnant widows were offered community help to cope with their grief and prepare for delivering a baby who would never know his or her father.