New scientific research is shedding light on the debilitating condition known as hyperemesis gravidarum, an extreme form of morning sickness that affects around one in 50 pregnant women globally. While most expectant mothers experience some nausea, this severe illness can leave sufferers unable to eat, drink, or carry out daily activities, often requiring hospital care.
The Hormonal Culprit Behind the Sickness
For years, scientists believed the pregnancy hormone human chorionic gonadotropin (hCG) was responsible. However, a pivotal shift in understanding occurred about five years ago. Researchers now identify high levels of a hormone called GDF15 as the main driver of all morning sickness, including its most severe form.
A person's sensitivity to GDF15 is key. Women who naturally produce low levels of this hormone before pregnancy are far more sensitive to the surge produced by the placenta. This makes low pre-pregnancy GDF15 a significant risk factor for developing hyperemesis gravidarum.
Recognising and Managing a Debilitating Condition
The symptoms of hyperemesis gravidarum are severe and distinct from typical pregnancy nausea. Sufferers experience unrelenting vomiting and rapid weight loss, often shedding more than 5% of their pre-pregnancy body weight. This leads to dangerous dehydration, electrolyte imbalances, and nutritional deficiencies, posing risks to both mother and fetus.
There is currently no cure, so treatment focuses on managing symptoms. This includes intravenous fluids for rehydration, anti-nausea medications safe for pregnancy, and nutritional support from dietitians. In the most severe cases, tube feeding or intravenous nutrition may be necessary.
Wider Health Impacts and Future Hope
The condition carries serious health implications. It increases the risk of pregnancy complications like placental abruption and pre-eclampsia. For the baby, there is a heightened chance of premature birth, low birth weight, and admission to neonatal intensive care. The mental health toll is also considerable, with increased risks of anxiety and depression requiring psychological support.
The discovery of GDF15's role offers a beacon of hope for future prevention and treatment. Scientists are exploring whether blocking the hormone's action during pregnancy could reduce nausea. Other theories focus on the potential to boost GDF15 levels before conception to build tolerance.
For now, improving awareness among both the public and health professionals remains crucial. Organisations like Hyperemesis Australia and the Centre Of Perinatal Excellence (COPE) provide vital resources and support for the thousands of women, including high-profile figures like the Princess of Wales, who endure this challenging condition.
