Is hyperemesis gravidarum only a medical condition? what is the relevance with psychiatric disorders?

Hyperemesis gravidarum (HG) affects 0.5–2% of pregnant women, and 10% of those diagnosed will require at least one inpatient hospitalization. HG characterized by intractable nausea and vomiting (NV), begins in the first trimester and causes weight loss during pregnancy, dehydration, electrolyte disturbance and nutrition deficiency. HG is differentiated from the NV common during pregnancy that affects approximately 75% of pregnant women by the need for hospitalization. The pathogenesis of HG has not yet been clearly identified. Some endocrine factors (such as human chorionic gonadotropin, estrogens, progesterone and thyroid hormone), gastrointestinal dysfunction, hepatic abnormalities, autonomic nervous dysfunction and psychosomatic causes may play a role in this medical condition. Despite the common psychiatric symptoms observed in women with HG, in these subjects, the psychiatric etiology is unclear. Many studies have evaluated the relationship between HG and psychiatric disturbances; however, most studies evaluated psychiatric symptoms based on self-report measures and had many limitations. Mazzotta et al. suggested that depressive symptoms in pregnant women were associated with more severe NV. Tan et al. showed that anxiety and depressive symptomatology is common in HG and that risk factors can be identified. However, psychiatric symptom scales were used in these studies, and these scales have low clinical value. A retrospective study reported that women with HG had more frequent psychiatric diagnoses preceding the pregnancy compared to the control subjects. In a clinic-based study, Uguz et al. reported that the prevalence of any mood disorder and any anxiety disorder in women with HG was 15.4% and 36.5%, respectively. Moreover, the researchers determined that 36.5% of the patients with HG had at least one personality disorder. In a recent prospective study based on psychiatric interviews, Annagur et al. reported that psychiatric disorders continued throughout the pregnancy in two thirds of the women who had HG and a psychiatric diagnosis. Moreover, the researchers suggest that psychiatric disorders may play a significant role in the etiology of HG. They presented a potential connection between HG and anxiety disorders and major depressive disorder. Additionally, the NV symptoms in women with HG and a psychiatric disorder may persist during pregnancy. In conclusion, HG is a medical condition that has a psychiatric etiology as much as a genetic and hormonal etiology. Recent studies’ findings show that psychiatric disorders may play a significant role in the etiology of HG. We can say that there are a potential connection between HG and anxiety disorders and MDD. Despite the common belief that NV is a phenomenon of early pregnancy, NV symptoms can persist into the third trimester. Additionally, the NV symptoms in women with HG and psychiatric disorder may persist during pregnancy. Women with persistent NV during pregnancy should be evaluated in terms of psychiatric disorders as much as their medical conditions. Psychiatric liaison is important in these women to promote optimal management, care and support for these women. Further study should focus on the effective treatment measures and the neonatal outcomes of women with HG and psychiatric disorders.