Scientists may have found the cause of morning sickness

Pregnancy is an exciting time, full of hope for the future — until the morning sickness begins. Bouts of nausea and vomiting can leave many pregnant women not just fatigued, but sometimes too weak to stand.

That’s how it was for geneticist Marlena Fejzo, who would become “so ill that she couldn’t move without vomiting,” she told the New York Times.

Fejzo suffered from the the most severe form, “hyperemesis gravidarum, characterized by relentless vomiting that can lead to malnutrition, weight loss and electrolyte imbalance that endanger the health of both the mother and fetus,” the Times wrote.

Although Fejzo, from the University of Southern California Keck School of Medicine, was unable to work for eight weeks and needed IV fluids for dehydration, her doctor told her the sickness was all in her head.

During her second pregnancy, Fejzo’s sickness was even worse. Doctors eventually diagnosed her with hyperemesis gravidarum, spurring the researcher to find a cause for the condition.

After decades of studies, Fajzo and her team believe they have found the cause. The researchers believe the hormone GDF15, which was first detected in high levels in pregnant women in the 2000s, acts on the brain to induce vomiting.

“Our findings place GDF15 at the mechanistic heart of (nausea and vomiting in pregnancy) and HG and clearly point the way to strategies for its treatment and prevention,” the researchers wrote in their preprint, which hasn’t been peer-reviewed yet.

“We can now conclude with confidence that higher circulating levels of GDF15 in maternal blood are associated with an increased risk of HG,” the team wrote.