A new study has shown why seven in 10 women experience nausea and vomiting during pregnancy – and why some women become so sick they need to be admitted to hospital.
It is caused by GDF15, a hormone produced by the foetus. The new study suggests it could be prevented by exposing mothers to GDF15 ahead of pregnancy to build up their resilience.
Hyperemesis gravidarum, or severe vomiting, is the commonest cause of admission to hospital of women in the first three months of pregnancy. Widespread ignorance of the disorder, compounded by fear of using medication in pregnancy, mean that many women with this condition are inadequately treated.
The international team from the University of Cambridge, Scotland, the USA and Sri Lanka used a combination of approaches including human genetics, new ways of measuring hormones in pregnant women’s blood, and studies in cells and mice.
They found that a woman’s sensitivity to GDF15 is influenced by how much of it she was exposed to prior to pregnancy. For example, women with beta thalassemia, who have naturally very high levels of GDF15, experience little or no nausea or vomiting.
Professor Stephen O’Rahilly, University of Cambridge, said: “Knowing this gives us a clue as to how we might prevent this from happening. It also makes us more confident that preventing GDF15 from accessing its highly specific receptor in the mother’s brain will ultimately form the basis for an effective and safe way of treating this disorder.”
Co-author Dr Marlena Fejzo from the Department of Population and Public Health Sciences at the University of Southern California, added: “Hopefully, now that we understand the cause of hyperemesis gravidarum, we’re a step closer to developing effective treatments to stop other mothers going through what I and many other women have experienced.”