• Posted September 23, 2025

Severe Pregnancy Symptoms Increase Risk for Mental Health Problems

Extreme pregnancy symptoms like excessive nausea and vomiting can dramatically increase a woman’s risk for mental health and neurological problems, a new study says.

Women diagnosed with hyperemesis gravidarum (HG) were more than 50% as likely to develop a range of 13 conditions that included postpartum psychosis and post-traumatic stress disorder, researchers reported Sept. 18 in The Lancet Obstetrics, Gynaecology, & Women’s Health.

They also had a nearly tripled risk for postpartum depression, as well as a more than doubled risk for eating disorders, researchers found.

“Many pregnant women experience nausea and vomiting but for women with HG this occurs at a level which is far from ‘normal’ and as such it can be profoundly debilitating,” lead researcher Hamilton Morrin said in a news release. Morrin is a doctoral fellow at the Institute of Psychiatry, Psychology and Neuroscience at King’s College London.

Hyperemesis gravidarum isn't simple morning sickness. Women with the condition experience prolonged and severe nausea and vomiting, leading to dehydration and weight loss, researchers said in background notes.

Hyperemesis gravidarum affects just under 4% of all pregnancies, and is the most common cause of hospitalization in the first trimester of pregnancy, researchers siad.

Most cases resolve from the second trimester, but it can leave women feeling anxious, isolated and unsure of their ability to cope with the rest of their pregnancy.

For the study, researchers analyzed data on nearly 477,000 women diagnosed with HG in 18 high-income and middle-income countries. The women had an average age of 27.

The team reviewed women’s health records for signs of 24 mental health and neurological disorders.

Results also showed that women had a doubled risk of Wernicke’s encephalopathy, a neurological condition caused by vitamin B1 deficiency, and for refeeding syndrome, complications that occur when a malnourished person is provided food too quickly.

“Many of these conditions would warrant urgent referral to specialist services for urgent assessment and treatment to ensure safety of mother and child,” Morrin said.

Results also showed that women with mild HG might be at greater risk for mental health problems, compared to those with HG so severe they suffer from malnutrition or dehydration.

As a result, the researchers recommend that all women with HG be screened for psychological problems, regardless of the severity of their symptoms.

“The severity of HG does not directly correlate with the degree of impact on mental health, and as clinicians, we have a responsibility to ensure these women receive adequate integrated care across both physical and mental health,” Morrin said.

Senior researcher Dr. Thomas Pollak, a clinical reader and consultant neuropsychiatrist at King’s College London, agreed.

“Until recently, there has been something of a disconnect between how the medical community has regarded the mental health impact of HG and how women themselves describe their experience,” he said in a news release.

“Our findings show that this gap is not only real but can be very serious,” Pollak continued. “HG can be associated with severe psychiatric disorders that require urgent recognition and joined-up physical and mental health care from the very start of pregnancy.”

More information

The American Pregnancy Association has more on hyperemesis gravidarum.

SOURCE: King’s College London, news release, Sept. 18, 2025