SEVERE pregnancy sickness is more than a physical ordeal. A new Finnish study has revealed that hyperemesis gravidarum is strongly associated with both pre-pregnancy and post-pregnancy depression, suggesting a deeper biological and psychological connection between the two conditions.
The Link Between Hyperemesis Gravidarum and Mental Health
Hyperemesis gravidarum is an extreme form of nausea and vomiting that can lead to dehydration, weight loss, and hospitalisation during pregnancy. While often dismissed as a physical complication, emerging evidence now shows that it may also carry serious mental health implications. Previous research into the relationship between hyperemesis gravidarum and depression has produced conflicting results, prompting the need for large-scale, population-based data. This latest national study aimed to clarify the association and shed light on the long-term psychiatric risks faced by affected women.
National Data Reveal a Strong Association
In this nationwide Finnish register-based controlled study, researchers analysed data from 437,465 women with pregnancies resulting in delivery between 2005 and 2017. After exclusions, 4,265 women were identified with hyperemesis gravidarum and compared with 302,663 women without the condition. Pre-pregnancy depression was significantly more common among those with hyperemesis gravidarum (8.8% vs 1.0%), with an adjusted odds ratio (AOR) of 5.2 (95% CI 4.3–6.3; p<0.0001). Post-pregnancy depression was also more frequent (4.9% vs 1.0%; AOR 3.6, 95% CI 3.0–4.4; p<0.0001). Moreover, women with hyperemesis gravidarum developed depression sooner after delivery, on average 3.3 years compared with 4.5 years in the control group.
Implications for Clinical Care
These findings highlight the bidirectional relationship between hyperemesis gravidarum and depression, pointing to possible shared biological mechanisms and a lasting mental health burden. The authors stress the importance of systematic psychiatric screening during and after pregnancy and the need to assess a woman’s lifetime history of depression as part of reproductive care. Closer collaboration between obstetric, psychiatric, and primary care services could improve outcomes for patients, ensuring early intervention and sustained psychological support for those affected by this debilitating condition.
Reference
Terävä-Utti E et al. Association between hyperemesis gravidarum and depression: a national register-based controlled study in Finland. The Lancet Psychiatry. 2025;12(11):841-51.
