Washington: American and international scientists report a hormone link that may explain why many women experience severe illness during early pregnancy.
Nausea and vomiting are common during pregnancy, and some women experience more severe complications including dehydration. Hormones produced by the developing uterus are implicated in causing nausea and vomiting; in extreme cases women may require hospitalization. This condition, known as hyperemesis gravidarum, can endanger both mother and baby.
Estimates suggest roughly 1–3 in 100 pregnant women develop hyperemesis gravidarum. Symptoms can include extreme nausea, frequent vomiting (some mothers report dozens of episodes per day), weight loss, dehydration, and adverse mental effects.
To investigate the cause, researchers from the University of Cambridge collaborated with teams in Scotland, the United States, and Sri Lanka. Their study, published in the journal Nature, found that the severity of pregnancy sickness is related to the amount of a hormone produced by the uterus. Higher production of the hormone corresponds with stronger symptoms.
Importantly, the study indicates that women with naturally lower pre-pregnancy levels of this hormone appear more vulnerable to sharp rises in a hormone known as GDF-15 during the first trimester. The research links increased GDF-15 with higher rates of nausea and hyperemesis.
According to reports, the researchers cited by outlets including The Guardian highlight the connection between GDF-15 and pregnancy sickness. Professor Sir Stephen O., co-director of the Wellcome/MRC Institute of Metabolic Science at Cambridge, explains that the developing uterus produces a hormone that triggers sickness symptoms; mothers who are more sensitive to it experience worse symptoms.
Professor Sir Stephen and colleagues suggest that blocking the hormone from reaching its receptor in the maternal brain could form the basis of a safe treatment. Scientists are continuing research aimed at preventing and treating hyperemesis gravidarum to improve outcomes for mothers and babies.
