Association of the Verbal Rating Scale-Measured Dysmenorrhea with Nausea and Vomiting in Pregnancy: A Retrospective Cohort Study

Objectives: Nausea and vomiting in pregnancy (NVP) is a common condition that reduces the quality of life by negatively affecting work and family life, physical and mental health, and economic wellbeing. However, its risk factors remain unclear. This study aimed to explore the association between NVP and verbal rating scale (VRS)-measured dysmenorrhea and to explore potential protective factors. Methods: This retrospective cohort study was conducted from June 2018 to December 2020 at Tongji Hospital in Wuhan. Information on baseline characteristics, pregnancy-related history, periconceptional micronutrient supplementation, and obstetric outcomes were collected. The severity of dysmenorrhea was assessed using VRS. Results: A total of 443 pregnant women were recruited and divided into the NVP group (n = 76) and the control group (n = 367). A significant association was observed between NVP and VRSmeasured dysmenorrhea (c2=10.038, P = 0.007). After adjusting for covariates, the association between moderate/severe dysmenorrhea and NVP remained significant (OR 2.384; 95% CI 1.104-5.148, P = 0.004). First-trimester docosahexaenoic acid supplement (OR 0.443; 95% CI 0.205-0.960, P = 0.039) may be beneficial in reducing the risk of NVP. Conclusions: Women with moderate to severe dysmenorrhea have a higher risk of experiencing NVP during the first trimester. Periconceptional docosahexaenoic acid supplementation may play a protective role.