Plasma serotonin levels are elevated in pregnant women with hyperemesis gravidarum

This study aimed to determine the association between serotonin and hyperemesis gravidarum. Plasma samples of 87 women in their first trimester pregnancies with HG (n = 28), morning sickness of pregnancy (n = 30) and control (n = 29) groups were obtained. Plasma levels of serotonin were compared between the groups, and the correlations with severity of symptoms using modified PUQE (Pregnancy Unique Quantification of Emesis) scoring, BMI, E2, hCG and TSH were calculated. When the groups were compared with respect to serotonin levels, the group with hyperemesis gravidarum was found to have significantly higher serotonin levels (p = 0.001). A significant positive correlation was found between the serotonin level and the PUQE score in all study subjects (r = 0.578, p = 0.0001). A serotonin threshold of > 277.58 ng/mL had a sensitivity of 75 %, specificity of 86.4 %, positive predictive value of 72.4 %, negative predictive value of 87.9 %, and a likelihood ratio of 5.53 (p = 0.0001). Our findings support the possible role of serotonin in the pathogenesis of hyperemesis gravidarum.