0209 GMT November 28, 2020
The Canadian researchers stressed that the risk is still very low: More serious heart defects were seen in only about 0.1 percent of newborns whose mothers had pre-eclampsia, HealthDay wrote.
Instead, the results suggest that pre-eclampsia and congenital heart defects share some underlying biological causes, explained Dr. Siobhan Dolan, medical advisor to the nonprofit March of Dimes.
"That's why this study is important," said Dolan, who is also a professor of clinical obstetrics and gynecology at Montefiore Medical Center, in New York City.
Dr. Nathalie Auger, the lead researcher on the study, agreed.
"Ultimately, we want to prevent both pre-eclampsia and congenital heart defects," said Auger, of the University of Montreal.
This is the first study to find an association between the two, Auger pointed out. The hope, she said, is that it will trigger more research to dig into the reasons behind the connection — and potentially find ways to cut the risks of both.
Anywhere from two percent to eight percent of pregnant women develop pre-eclampsia. The condition is marked by high blood pressure and other signs that a woman's organs, such as the kidneys and liver, are not functioning properly. Those signs include protein in the urine, severe headaches and vision problems.
Pre-eclampsia can have serious complications, such as preterm delivery and low birth weight. It also raises a woman's risk of seizures, coma and placental abruption, where the placenta separates from the uterus, sometimes causing life-threatening bleeding.
The exact cause of pre-eclampsia is unknown, but it's thought to involve abnormal development in the blood vessels that supply the placenta, Dolan explained.
Pre-eclampsia is typically diagnosed later in pregnancy, after the 20th week, and often in the third trimester. In contrast, the major fetal heart structures take shape early in pregnancy. So it seems unlikely that pre-eclampsia would be causing congenital heart defects, according to Auger.
Instead, the researchers suggested, underlying problems in new blood vessel development might contribute to both.
The findings are based on medical records from nearly two million infants born in Quebec between 1989 and 2012. Close to 73,000 mothers had pre-eclampsia.