Hyperemesis gravidarum (HG) affects about one-in-100 women and is characterised by severe nausea and vomiting in pregnancy, sometimes lasting the entire way through.
It can lead to dehydration and weight loss and result in hospitalisation for treatment.
Catherine, Princess of Wales, experienced HG during her pregnancies, raising awareness of the condition across the world.
The condition is linked to high rates of anxiety and depression in pregnancy and the commonly prescribed treatments are often ineffective.
A Flinders University study showed 54 per cent of women affected by HG considered terminating their pregnancy, while 90 per cent said they thought about not having more children.
The national survey of 289 women is one of the most comprehensive studies of the lived experience of HG in Australia.
The findings underscored the need for more compassionate, evidence-based care for pregnant women who experience HG, lead author Luke Grzeskowiak said.
"Hyperemesis gravidarum is not just morning sickness, it's a serious condition that can have devastating consequences for women's mental health, relationships and decisions about future pregnancies," associate professor Grzeskowiak said.
"Our study shows that many women are not getting the support or relief they need, and that's something we must urgently address."
More than half of those surveyed said HG had majorly disrupted their ability to work, care for children, maintain relationships and perform daily tasks.
Nearly 40 per cent had asked for an early induction of labour to end their pregnancy sooner due to the severity of their symptoms.
Only half of the women surveyed said commonly prescribed treatments were effective.
Ondansetron, doxylamine and corticosteroids were perceived as the most effective medications, yet many women said they had significant side effects, including constipation, sedation and impacted cognition.
Nearly one-third stopped using metoclopramide, another frequently prescribed drug, due to adverse effects.
"Women are often prescribed multiple medications in an attempt to manage their symptoms, but the reality is that many of these treatments come with their own burdens," Assoc Prof Grzeskowiak said.
"We need better evidence to guide treatment decisions and ensure women are supported to make informed choices."
Women's symptoms were too often dismissed as a "normal" part of pregnancy, but the condition was life-altering, Hyperemesis Australia founder Caitlin Kay-Smith said.
"We need to move away from a one-size-fits-all approach and toward personalised care that recognises the full impact of HG," she said.
10°C