Scientists Identify Genetic Markers for Severe Pregnancy Nausea
A breakthrough in genetic research has identified the genes responsible for the most severe forms of pregnancy-related nausea, offering new hope for millions of women worldwide. Researchers from the Keck School of Medicine of the University of Southern California (USC) have mapped the genetic drivers of hyperemesis gravidica (HG), a debilitating condition that transforms common morning sickness into an incapacitating illness.
While many pregnant women experience mild nausea, HG affects approximately 1 to 3 out of every 100 pregnancies (or about 2% of women). This condition is characterized by intense vomiting that makes eating extremely difficult and can lead to severe malnutrition and dehydration, posing significant risks to both the mother and the developing fetus. For years, the extreme distress caused by HG was often underestimated by medical professionals or incorrectly attributed to psychological factors.
The latest study, published in Nature Genetics, provides a biological foundation for the disorder. The international research team analyzed the genetic data of 10,974 women suffering from HG and compared them against more than 460,000 control subjects from diverse backgrounds, including European, Asian, African, and Latin American populations. This broad scope ensures that the findings are relevant across multiple global populations.
Building on previous work that identified the GDF15 hormone-encoding gene as a key factor in pregnancy nausea, researchers have now identified nine additional genes linked to the more severe HG form. Notably, six of these genes had never been associated with the condition before. This discovery clarifies that the intensity of nausea is tied to a woman’s sensitivity to the GDF15 hormone and the amount of this protein produced by the fetus.
This genetic mapping is a critical step toward moving beyond symptomatic relief toward targeted medical interventions. “Now that we know the cause of hyperemesis gravidica, we are closer to developing effective treatments to prevent other mothers from going through what I and many other women have experienced,” stated Marlena Fejzo, a researcher at the University of Southern California and one of the study’s leads.
By understanding the molecular origins of the disorder, healthcare providers can better diagnose the condition and develop prevention strategies. These findings underscore the importance of recognizing HG as a biological medical condition rather than a psychological one, potentially reducing the risk of hospitalization during the first months of gestation.
