New Light on Stillbirths

Placental conditions affect most stillborn births

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) A stillbirth is a traumatic event, and the underlying causes remain unknown in as many as half of them.

But new light is being shed on pregnancy conditions that contribute to infants who die during the second half of pregnancy. A new report shows that pregnancy disorders and conditions affecting the placenta cause about half of all stillbirths.

“Our study showed that a probable cause of death—more than 60%—could be found by a thorough medical evaluation,” says study co-author Dr. Uma M. Reddy of NICHD.

"Talk to your OB about a healthy pregnancy."

About one in 160 pregnancies nationwide result in stillbirth, the death of the baby after 20 weeks of gestation. The risk factors that have already been known to contribute, such as obesity, diabetes, high blood pressure or a previous pregnancy loss, only account for a small percentage of stillbirths.

The National Institutes of Health established the Stillbirth Collaborative Research Network (SCRN) to study the causes. Researchers at the network enrolled 614 women who delivered a stillbirth, and compared them with 1,816 live births.

Beginning with the start of pregnancy, the research team looked at factors that might raise the risk for stillbirth.

Results strongly linked stillbirth with several reproductive features that included having had a stillbirth or miscarriage in previous pregnancies, being a first-time mother, being overweight or obese, age 40 or older, AB blood type, smoking and a history of drug addiction.

All these risk factors were previously known or suspected, and only account for a small percentage of stillbirths.

The SCRN went on to do comprehensive medical evaluations of 512 stillborn babies to identify the causes of death in further detail, examining the placenta and doing an autopsy of the fetus.

Scientists identified a probably cause of death in 61 percent of the cases, and a probable or possible cause in 76 percent. Pregnancy or birth-related complications contributed to the largest proportion of stillbirths (29 percent), including preterm labor, premature rupture of the amniotic sac and abruption of the placenta.

African-American women were at higher risk of stillbirth than white or Hispanic women.

Reviewed by: 
Review Date: 
December 21, 2011
Last Updated:
December 22, 2011