Severe morning sickness linked to GDF15 hormone: Study

Severe morning sickness symptoms during pregnancy are likely linked to one specific hormone, according to a new study.

The scientific journal Nature, which published it's findings on Wednesday, found that nausea and vomiting, common symptoms during the first trimester of a pregnancy, are primarily caused by the GDF15 hormone — which is produced in fetal bone marrow.

“GDF15, a hormone acting on the brainstem, has been implicated in the nausea and vomiting of pregnancy (NVP) including in its most severe form, Hyperemesis Gravidarum (HG), but a full mechanistic understanding is lacking,” the study reads.

“Despite the fact that nausea and vomiting are symptoms which occur in most human pregnancies, are commonly disabling and, when severe, can be life-threatening, their etiology and pathogenesis have remained poorly understood,” the researchers added.

The mother's sensitivity to the hormone is determined by prior exposure, the experts explained. The authors said the discovery will aid in finding treatments for the condition.

“We now know that women get sick during pregnancy when they are exposed to higher levels of the hormone GDF15 than they are used to,” Marlena Fejzo, one of the main authors of the study, said.

In a news release, Fejzo explained that lowering the level of the hormone could be one way to combat morning sickness. Another way, according to the expert, could be to expose pregnant women to GDF15 prior to pregnancy to "prepare them" for the elevated levels.

“This study provides strong evidence that one or both of those methods will be effective in preventing or treating HG,” Fejzo, a clinical assistant professor at the Keck School of Medicine's Center for Genetic Epidemiology at the Keck School of Medicine, added.

Experts weighed the hormone in pregnant women's blood and monitored for genetic risk factors. The women who experienced hyperemesis — or debilitating symptoms that make it difficult to eat, drink or do daily activities — had significantly higher levels of the GDF15 hormone during pregnancy than those who had no symptoms.

“Hopefully, now that we understand the main cause of HG, we’re a step closer to developing effective treatments to stop other mothers from going through what I, and many other women, have experienced,” Fejzo said.

The breakthrough comes as accessibility to maternal health care has been on the decline as the mortality rate for pregnant mothers is on the rise. Data from the nonprofit organization March of Dimes released earlier this year found that in 2022 over 6.9 million people lived in areas where access to maternity care was challenging.

The organization also noted that only 45.7 percent of all of the counties in the U.S. have access to full maternity care.