Scientists identify single hormone that causes morning sickness, better treatment to come

Researchers have discovered that GDF15, a hormone that occurs in low amounts throughout the body but is generated at more significant levels during pregnancy, causes morning sickness.

Expectant mothers will be thrilled to know that relief for their morning sickness is in the works.

According to Fortune, researchers at the University of Southern California and the University of Cambridge discovered that GDF15 — a hormone in low amounts throughout the body but one generated at more significant levels in the placenta during pregnancy — causes morning sickness. 

Not every woman reacts severely to the hormone, which is why about 20 percent remain relatively unfazed. The most severe instances, called hyperemesis gravidarum, or HG, affect approximately 2 percent of women and necessitate hospitalization.

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Scientists have uncovered the single hormone that causes morning sickness in pregnant women: GDF15. (Photo: Adobe Stock)

“For the first time, this interaction between mother and fetus helps explain why some women get HG during some — but not all — of their pregnancies,” said the paper’s first author, Marlena Fejzo, a clinical assistant professor of population and public health sciences in the Center for Genetic Epidemiology at USC.

While Fejzo emphasized that more analysis is needed to confirm the findings, researchers noted that one reason certain pregnant women may not experience HG or even moderate morning sickness is that patients with the hereditary blood ailment beta thalassemia are primarily resistant to the phenomenon since their GDF15 levels are continuously increased.

Sometimes, a woman inherits a rare genetic mutation that results in persistently low levels of GDF15 throughout her body, but her baby does not. As a result, she will be exposed to more hormones than she is used to, which will most likely trigger morning sickness. If her child inherits the gene, she will unlikely acquire the illness.


Researchers are now considering reducing the hormone levels in pregnant women and exposing women to GDF15 before pregnancy to prepare for increased levels later. Fejzo’s team intends to find out if metformin, an oral diabetic medication that raises GDF15 levels, may be used to help women with a history of HG.

They also hope to examine an additional class of medications that are already undergoing testing in clinical trials for cachexia, a metabolic disease that causes significant weight loss, and nausea and vomiting in cancer patients. The medications prevent GDF15 from attaching to its receptor in the brain.

“Hopefully,” Fejzo concluded, Fortune reported, “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.”

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