Morning sickness: Huge breakthrough in search of cure for debilitating condition suffered by pregnant women

A morning sickness drug that women start taking before they get pregnant could be on the way, scientists say. Up to 70 per cent of women suffer the misery of nausea and vomiting when they are expecting a baby. Scientists previously found a hormone that appeared to trigger morning sickness in the brain but have spent almost a decade trying to understand how it works. Their breakthrough centres around the discovery that this hormone, called GDF15, needs to be at a high level in a pregnant woman’s body. In order for a woman to suffer from morning sickness, however, she also needs to have had a low level of the chemical before pregnancy. It is believed that a sudden surge in the hormone is what causes the nausea and vomiting. This discovery paves the way for a drug that women could take before they even conceive, to top up their GDF15 so they are far less likely to develop morning sickness. Metformin, currently given to people with type 2 diabetes, is a promising candidate, and researchers are preparing to test it in women as early as next year. Such a pre-pregnancy drug would be a lifeline for women — many of whom suffer through morning sickness and are afraid to take anti-sickness medications during pregnancy despite evidence for their safety. It could also provide hope for hyperemesis gravidarum (HG), a debilitating form of sickness that affects up to three per cent of pregnancies. Famously suffered by the Princess of Wales, this life-threatening condition can cause sickness many times a day, with some women ending up being hospitalised with dehydration. Professor Sir Stephen O’Rahilly, from the University of Cambridge, who led the study said: “Our findings convincingly demonstrate the role of the hormone GDF15, and should transform the way we treat morning sickness or hyperemesis gravidarum, to reduce the suffering of women.” The study, carried out by an international team of scientists and published in the journal Nature, suggests building up a woman’s tolerance to the hormone before pregnancy, by giving her a drug containing it, could help prevent morning sickness. Metformin is likely to be trialled in women who have had HG previously. Preventing the hormone from triggering nausea, using an injection, could be another treatment approach, although this would need to be safe. It is likely morning sickness was necessary in hunter-gatherer times, to put women off foods that may have been toxic to their babies, but it no longer serves a function.