Longer Pregnancies = Lower Infant Mortality Rates

The Scoop

It's a topic no mom really wants to think about, but according to a study in the journal Obstetrics & Gynecology, infant mortality rates can be reduced by as much as 50 percent when women wait until at least 39 weeks—rather than 37 weeks—to give birth.

What's the connection? Carried out by researchers at the National Institutes of Health, the Food and Drug Administration (FDA), and the March of Dimes, the study looked at birth data from more than 46 million infants born in the US between 1995 and 2006. As the New York Times reports, in that period, the proportion of infants born before 39 weeks increased to nearly one in three births, due largely to an increase in elective, non-medically necessary Cesarean deliveries. Alarmingly, researchers found that infants born at 37 weeks were twice as likely to die in the first year of life, with 3.9 deaths per 1,000 births, compared to those born after 39 weeks, with less than two deaths per 1,000 births.

Yes, it's scary. But the message that public-health agencies and professional medical groups want to spread here is this: early elective deliveries are a bad idea. "Up until the last several years, we thought term pregnancies between 37 and 41 weeks were the same," says Alan Fleischman, medical director at the March of Dimes, in an interview with Time magazine. "This is not the case. ... The new data makes us pause and realize we ought not intervene unless there's a very good medical reason."

Your Pregnancy

The argument for allowing elective deliveries before 40 weeks has rested in the textbook fact that pregnancies are considered "term"—complete—at 37 weeks. But "women need to know that all 'term' pregnancies are not alike," says Dr. Uma M. Reddy, the study's lead author and a medical officer with the pregnancy and perinatology branch at the National Institute of Child Health and Human Development (via the NY Times).

Bottom line if you are considering an early elective delivery for the sake of your work schedule, visiting relatives, or other non-medical reasons? Researchers hope moms reconsider. "If the pregnancy is uncomplicated, babies should not be delivered before 39 weeks," advises Dr. Reddy.