Vitamin D affects how your immune system works, and plays a role in controlling certain types of inflammation, including the type that leads to autoimmune diseases. It’s common for people with lupus to have low levels of vitamin D. In a recent study, researchers examined how vitamin D levels impact pregnancies among women with systemic lupus erythematosus (SLE) and found risks for adverse pregnancy outcomes, including miscarriage, preterm delivery, and small gestational age, were evident at higher and lower levels of vitamin D. 

Researchers analyzed 260 pregnancies of women with SLE in the Hopkins Lupus Cohort to examine the association between 25 hydroxy-vitamin D levels and adverse pregnancy outcomes. Each woman was prescribed prenatal multivitamins and was seen every six weeks during their pregnancy with assessment of vitamin D levels at each visit. Study participants were divided into six separate groups based on their vitamin D levels. A U-shaped curve association was observed between vitamin D levels and adverse pregnancy outcomes, meaning that both low levels and high levels of Vitamin D led to adverse outcomes. Women at the highest risk were those who had the lowest and highest levels of vitamin D, however the increased risk among those at the highest level was not statistically significant. Those at the lowest risk had vitamin D levels between 40 and 59 ng/mL (normal range: 20-50 ng/mL). However, study results showed the most significant association was between vitamin D levels in the second trimester and increased chances of premature delivery. 

Based on the study findings, monitoring vitamin D levels through pregnancy is recommended to keep women with SLE within the best range. Learn more about lupus and pregnancy.

Read the study