Stillbirth is heartbreaking tragedy for parents, but exactly what raises the risk of it remains elusive.
Certain health conditions in a pregnant woman can be a factor, but new research came up with a surprising finding: Stillbirth risk appears to be inherited through male members of the family on either side.
"Stillbirth is one of those problems that is so tragic and life-changing," said study co-author Dr. Jessica Page, an assistant professor in the department of obstetrics and gynecology at University of Utah Health and Intermountain Healthcare.
"It is especially frustrating when you don't have a good answer for why it happens," she said in a university news release. "This knowledge may give us the opportunity to change how we risk stratify people and reduce their risk through prevention."
In the study, the scientists looked at 9,404 stillbirths and 18,808 live births in Utah that happened between 1978 and 2019. The cases were recorded in the Utah Population database, a genealogical resource linked to health, birth and death records.
Researchers found that 390 families had an excess number of stillbirths over multiple generations, which suggested there could be genetic causes for stillbirth.
The research team then compared incidence of stillbirth among first-, second- and third-degree relatives of babies from affected families with the same relatives from unaffected families. Their analysis revealed that an increased risk for stillbirth was passed down through male relatives, a trend that had never been seen before, according to the study.
"We were able to evaluate multigenerational trends in fetal death, as well as maternal and paternal lineages, to increase our ability to detect a familial aggregation of stillbirth," said study lead author Tsegaselassie Workalemahu, also from the department of obstetrics and gynecology at University of Utah Health.
"Not many studies have examined inherited genetic risk for stillbirth because of a lack of data," he said in the release. "The Utah Population Database [UPDB] allows for a more rigorous evaluation than has been possible in the past."
Identifying specific genes that increase the risk of stillbirth is an important next step that could one day lead to better diagnosis and prevention. Understanding patterns in families may help genetic counselors advise families about their risk, Workalemahu said.
"Studying pregnancy provides the opportunity to improve the health of future generations," he said.
Stillbirth is more common in the United States than many people realize, occurring in 1 in 165 births among babies that are 20 weeks or older. About 1 in 3 cases of stillbirth are unexplained. Other risk factors include high blood pressure during pregnancy, preeclampsia and diabetes in the mother.
Study limitations include a lack of diversity because the database population was largely of northern European descent.
"Stillbirth rate reduction has been slow in the U.S. and we think many stillbirths may be potentially preventable," Page said. "This is motivating us to look for those genetic factors so we can achieve more dramatic rate reduction.”
The findings were published recently in the journal BJOG.
The U.S. Centers for Disease Control and Prevention has more on stillbirth.
SOURCE: University of Utah, news release, Oct. 18, 2022