Hope for pregnant women as hormonal discovery hints at treatment for morning sickness

Morning sickness is something which pregnant women have had to endure for far too long, but a discovery made by an international team of scientists is causing a great deal of interest and may lead to new treatments and prevention of the most severe form of morning sickness, hyperemesis gravidarum.  This new study (https://www.nature.com/articles/s41586-023-06921-9) published in leading scientific journal Nature has been welcomed by the Royal College of Obstetricians and Gynaecologists (RCOG), who describe this study as “a major advance in understanding the cause of pregnancy sickness”.   According to RCOG, 70% of pregnancies are affected by nausea and vomiting, with 1-3% being severe, and this is the most common cause of admission to hospital for women in the first three months of pregnancy.  As such, any treatment which can prevent or lessen these symptoms will come as welcome relief.

It has been known that a hormone which acts on the brainstem called GDF15 is associated with nausea and vomiting during pregnancy, but the mechanism by which this occurred was not clear. The researchers have reported that foetal production of GDF15 as well as how sensitive the mother is to this hormone are key risk factors in the likelihood of facing severe morning sickness. Higher levels of the hormone, which is primarily produced in the foetal-placental unit, in the mother's blood are associated with severe morning sickness.  Furthermore, low levels of the hormone when the mother is not pregnant also increase the risk of severe morning sickness. Interestingly, women with beta-thalassaemia are somewhat protected from severe morning sickness due to the chronically high levels of GDF15 that are symptomatic of beta-thalassaemia.  Furthermore, mouse models indicate that it is possible to desensitize the body to this hormone, hinting at the possibility of a new form of pre-emptive treatment.

The new insight into the causes of severe morning sickness points to ways by which morning sickness can be treated.  For instance, blocking the action of GDF15 during pregnancy should help mothers suffering from morning sickness.  Another option is to increase the levels of GDF15 in the mother prior to pregnancy in order to desensitize her to the effects of GDF15.  This could be achieved by providing GDF15 to the mother ahead of pregnancy or by prescribing a drug called metformin, which increases GDF15 levels in humans.  Of course, any such treatments will require extensive safety testing and further experimentation, and there may be entirely new drugs developed to control the levels or activity of GDF15

It will be very interesting to see how this research progresses and whether it leads to new treatments for severe morning sickness.  I will be supporting a research project based on these findings as they seem to hold a great deal of promise.