Newly published research shows that stillbirth can be inherited and tends to be passed down through male members of the family. That risk preferentially comes from the mother’s or father’s male relatives—their brothers, fathers, grandfathers, uncles, or male cousins. But the odds of a couple losing a baby to stillbirth are even greater when the condition comes from the father’s side of the family.
The results, published in BJOG, examine the health histories of families over multiple generations.
In the U.S., stillbirth is more common than many people realize, occurring in 1 in 165 births among babies that are 20 weeks or older. The risk goes up when the mother has certain health conditions such as gestational hypertension, preeclampsia, or diabetes, but the causes of as many as 1 in 3 cases still go unexplained.
To understand other risk factors contributing to stillbirth, the scientists examined 9,404 stillbirth cases and 18,808 live birth controls between 1978 and 2019 that were represented in the Utah Population Database, a genealogical resource linked to health, birth, and death records. They found that 390 families had an excess number of stillbirths over multiple generations, suggesting there are genetic causes of stillbirth.
By comparing incidence of stillbirth among first-, second-, and third-degree relatives of babies from affected families with the equivalent relatives from unaffected families, the scientists identified familial risk in related individuals. Their analysis revealed that an increased risk for stillbirth was passed down through male family members, a trend that had not been seen before.
The population in the UPDB has similar genetic diversity to the U.S. population of northern European descent and may not be generalizable to the general U.S. population. Future studies will need to determine whether the trends hold true among people of different races and ethnicities.
