In a new study, researchers have found that vitamin D levels in early pregnancy may relate to symptoms of depression and anxiety.
Depression and anxiety are relatively common during pregnancy, with an estimated 15-30% prevalence among women in the United States. Previous research suggests that mood disorders during early pregnancy may increase the risk for smoking during pregnancy, complications such as preeclampsia during pregnancy, and poor mental health after birth.
Vitamin D has been shown to play a role in certain mood disorders, so it is hypothesized that a potential relationship between vitamin D status and mood disorders exists during early pregnancy. Understanding this relationship may help to reduce the risk of mood-related risks and complications.
Recently, researchers from Seattle and Boston collaborated on a study to determine if vitamin D was related to depression and anxiety symptoms among women in early pregnancy.
They recruited 498 women who had been pregnant for an average of 15.4 weeks. They measured the women’s vitamin D levels as well as assessed symptoms of depression and anxiety using Depression, Anxiety, and Stress Scales (DASS-21) and Patient Health Questionnaire Depression Module (PHQ-9).
DASS-21 and PHQ-9 are tools used to assess symptoms of depression, anxiety, stress and other mental health disorders. Higher scores in both assessments indicate more severe symptoms.
The researchers found that about 12% of the women had moderate anxiety and depression symptoms. Every 1 ng/ml decrease in vitamin D levels was related to a 0.043 and 0.040 increase in DASS-21 and PHQ-9 scores, respectively. Women in the group with the lowest vitamin D levels had an increase of 1.11 in PHQ-9 scores compared to women in the group with the highest levels.
The results also showed that lower vitamin D levels were related to more severe depression symptoms among women who reported no physical activity. This relationship did not exist in women who did report physical activity.
“In sum, our findings suggest that vitamin D may be related to self-reported symptoms of depression in early pregnancy independent of factors including: BMI, skin color, season, age, and smoking,” the researchers concluded.
“This relationship may be strongest among those who report no physical activity.”
The researchers call for future studies to look at the relationship between vitamin D and depressive symptoms throughout the course of pregnancy and to further explore the role of physical activity in this relationship.