Is there a correlation between the severity of symptoms and vitamin D levels in pregnancy with hyperemesis gravidarum?

Objective: This study aimed to investigate the relationship between serum vitamin D levels and the severity of symptoms in individuals with hyperemesis gravidarum (HG).

Materials and methods: A cohort of eighty patients exhibiting vomiting three or more times daily, positive ketones on complete urinalysis, and oral feeding difficulties were recruited. Symptom severity was assessed using the 8-question Rhodes index, categorizing patients into non-symptomatic, mild, moderate, and severe groups. Serum vitamin D levels were measured using venous blood samples; a deficiency was defined as less than 10 ng/mL, an insufficiency as 10-20 ng/mL, and a normal level as more than 20 ng/mL.

Results: The distribution of symptom severity revealed 14 (17.5%) with mild, 38 (47.5%) with moderate, and 28 (35%) with severe symptoms. Groups showed no significant differences in demographic or obstetric characteristics except for ketone positivity rates (p<0.05). There was a significant difference in vitamin D levels between the severity groups: mild symptoms (32.12±4.02 ng/mL), moderate symptoms (19.98±6.37 ng/mL), and severe symptoms (8.11±3.06 ng/mL) (p<0.001). Vitamin D and the Rhodes index mean score showed a significant negative relationship (r=-0.844, p=0.001). With 96.4% sensitivity and 89.5% specificity, receiver operating characteristic analysis showed that symptom intensity rose when blood vitamin D levels were less than 11.54 ng/mL.

Conclusion: These results highlight a negative relationship between the severity of HG symptoms and serum vitamin D levels. Screening pregnant women with nausea, vomiting, and severe symptoms for serum vitamin D deficiency is recommended. Appropriate pre-pregnancy treatment should be initiated for those deficient or insufficient in serum vitamin D to potentially alleviate HG symptom severity and frequency.