Hyperemesis gravidarum has nothing to do with a little morning sickness – unpleasant, certainly – but which eventually dissipates. This disease is a real daily hell where eating and drinking a glass of water becomes an insurmountable ordeal. Many pregnant women suffering from this illness are also hospitalized.
Having remained in the blind spot of medical research for a long time, this pathology nevertheless affects up to 10% of future mothers. But today, the tide is finally turning. A massive study published on April 14 in the journal Nature Genetics and relayed by the online magazine Live Science provides a clear answer: genetics is at the heart of the problem and more precisely a gene called GDF15.
This gene controls a hormone that acts directly on the vomiting center in our brain. According to researchers, some women have genetic variations that make them either more sensitive to this hormone or carry abnormally high levels. For the Dr Andrew Housholder, cited in the study, this discovery is fundamental. “This should finally put an end to discussions presenting hyperemesis gravidarum as simply sensitivity to human chorionic gonadotropic hormone (hCG) or estrogen”he explains.
The most fascinating aspect of this research is the connection made with other chronic diseases. By analyzing data from more than 400,000 women, the team led by Marlena Fejzo, from the University of Southern California, discovered that hyperemesis gravidarum shares, for example, common roots with type 2 diabetes. The study, which is based on global data including European, Asian and African populations, shows that a gene called TCF7L2 is also involved.
A preventive treatment being tested
This gene regulates a hormone involved in insulin and appetite, the same one that is targeted by new treatments called GLP-1, popular for obesity. This discovery suggests that hyperemesis gravidarum is not just a matter of gynecology, but a complex metabolic disorder. Knowing that these mechanisms are linked to the management of sugar and insulin allows scientists to explore avenues for already existing medications to relieve patients.
Currently, there is no treatment specifically approved by health authorities for hyperemesis gravidarum. Doctors often tinker with traditional anti-nausea medications, which are often not very effective. But thanks to the identification of GDF15, that could quickly change. Clinical trials are already in the works to test a preventative approach: using metformin, a well-known diabetes drug, before pregnancy even begins.
Genes linked to memory
The idea is to desensitize the woman’s body to the hormone GDF15 before conception. If the body gets used to higher levels beforehand, it could react less violently during the hormonal peak of the first trimester. Marlena Fejzo, who herself suffered from this pathology and made it the battle of her life, confides: “This will be useful for exploring new avenues of therapy and better ways to predict, diagnose and potentially prevent hyperemesis gravidarum in the future.”
The study also highlights genes linked to memory and learning. This could explain why women with hyperemesis gravidarum develop such powerful and long-lasting food aversions. The brain registers the targeted food as poison in order to protect the body, creating actual psychological trauma. Validating the genetic cause of the disease also relieves the guilt of mothers who do not enjoy their pregnancy as they should according to social standards.
By identifying ten genes in total, scientists prove that hyperemesis gravidarum is a complex multisystem disease, pushing the medical profession to take this pathology seriously. A giant step forward for reproductive medicine, but also for the recognition of female pain.
The final objective is simple: to ensure that hyperemesis gravidarum becomes a disease that we know how to manage and support, and no longer an inevitability. Researchers hope that these genetic markers will soon make it possible to screen women at risk before they become pregnant to establish a personalized care protocol from the first weeks of pregnancy, avoiding emergency hospitalizations or severe dehydration.
