Tests on fetus can help explain stillbirth, study says
Stillbirths are about as common as infant deaths, but they remain a largely unacknowledged loss.
Shining light on the difficult subject — by doing extensive testing — can help parents find closure and possibly avoid another loss, according to Dr. Robert Silver, who is part of a national network created to reduce stillbirths.
His research shows that performing an autopsy, evaluating the placenta and genetically testing the fetus can provide a probable or possible cause of death in 76 percent of the stillbirths studied, according to an article he wrote for the Journal of the American Medical Association, released Dec. 13.
“Patients are often reluctant to do testing. They think it’s not going to make any difference,” said Silver, who is in charge of the University of Utah’s maternal-fetal medicine program. “Often doctors will attribute the loss to a very superficial finding, like a cord wrapped around the neck, and not dig deeper.”
In fact, the study of 512 stillborns — a fetal death in the second half of pregnancy — found the most common causes were obstetric complications, including preterm labor and premature rupturing of the amniotic sac, accounting for 29 percent of the deaths.
“Those are often overlooked,” Silver said. “We focus on those as cause of preterm births. But they also cause stillbirths. Attacking those problems is going to also help with stillbirth.”
African-American women, whose rate of stillbirths is two times higher than white women, also have double the rate of preterm births, according to the study.
The Stillbirth Collaborative Research Network was created by the federal government in part to address the disparity. It tracked nearly all stillbirths that occurred from 2006 to 2008 in selected counties in five states. It compared the stillborns with live births in the same areas.
Five hundred parents consented to complete postmortem exams, which included maternal interviews, reviews of prenatal medical records, autopsies, placental evaluations, karyotyping to check for chromosomal abnormalities and other tests.
Abnormal placentas accounted for 24 percent of the deaths Other causes included genetic or structural problems in the fetus, infections, umbilical cord abnormalities, hypertensive disorders and maternal medical complications.
Other studies have shown that half to 90 percent of stillbirths can be prevented.
“Stillbirths in black women are different than stillbirths in white women,” Silver said, noting that they are more likely to happen earlier in pregnancy, during labor and to be associated with infections or obstetric complications.
Knowing the cause of the stillbirth can help doctors prevent it in a subsequent pregnancy: They may give progesterone to avoid preterm labor or give a low-dose blood thinner to prevent placental problems, he said.
Other maternal risk factors that the network found in a separate JAMA article can’t be changed, including having prior stillbirths, AB blood type, being black and being 40 or older.
The study also found that mothers that have diabetes, are obese or have a history of drug use or cigarette smoking before pregnancy are at higher risk. However, those factors, including the demographic ones, account for a small portion of stillbirths.
That means any interventions developed must target all pregnant women, Silver said.
For now, he urges doctors to perform the three tests that will find most causes of stillbirths.
Autopsies are free to patients.
Placental exams are usually covered by insurance but would cost a “few hundred dollars” and genetic tests are $800, he said
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Contact Heather May at hmay@sltrib.com. For more stories visit scrippsnews.com.