New Study Reveals Hormonal Cause of Morning Sickness and Potential Treatments

Recent research by the University of Southern California (USC) and the University of Cambridge identifies the key cause of nausea and vomiting during pregnancy, commonly known as morning sickness, linking it to a specific hormone produced by the fetus.

According to researchers, morning sickness impacts around 80 percent of pregnant women. A more severe form, known as hyperemesis gravidarum (HG), affects an additional two percent and can result in significant weight loss, dehydration, and even hospitalization. Until recently, the exact cause of these symptoms was unclear. However, a growing body of evidence points to a connection between morning sickness and GDF15, a hormone generated in the placenta whose levels rise significantly during pregnancy.

The study, published in Nature, indicates that a mother's sensitivity to GDF15 plays a significant role in the severity of morning sickness. The findings showed that women with lower pre-pregnancy exposure to GDF15 tend to experience more intense symptoms. The implication of this sensitivity could lead to new preventative measures or treatments.

Researchers utilized genetic analyses, blood tests, and animal studies to solidify this connection. They also found that certain conditions like beta thalassemia, which result in higher GDF15 levels, seem to protect against severe pregnancy sickness.

“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 Marlena Fejzo, PhD, a clinical assistant professor of population and public health sciences in the Center for Genetic Epidemiology at the Keck School of Medicine and the paper’s first author.

The study presented two potential approaches to mitigating symptoms of morning sickness. The first involved "priming" women with GDF15 before pregnancy to prepare their bodies for the hormone surge. The second focused on safely lowering GDF15 levels during pregnancy, as evidenced by healthy births where both mother and fetus had low GDF15 due to a genetic mutation.

While these results offer hope for the treatment of morning sickness, Dr. Fejzo said more research is needed to confirm the findings. Future will aim to validate these methods in human trials, including the use of drugs like metformin, known to increase GDF15 levels, and others that prevent GDF15 from binding to brain receptors.

For integrative healthcare practitioners, these findings offer new insights and possible avenues for treatment, bringing hope to many expectant mothers who suffer from what can be a debilitating condition.

“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,” Dr. Fejzo said.