A placebo-controlled trial published on Jul. 19 found that vitamin D supplementation did not significantly reduce persistent endometriosis symptoms in women already receiving hormonal therapy.
Researchers conducted a randomized controlled trial to assess whether adding vitamin D to dienogest (Verogest) therapy could improve outcomes for women with endometriosis. After eight weeks, participants who received vitamin D had numerically lower adjusted mean scores on pain measures compared to those given a placebo, but the differences were neither statistically significant nor clinically meaningful.
The study included 66 married and sexually active women diagnosed with symptomatic endometriosis and vitamin D insufficiency. Participants were randomly assigned to receive either 4,000 IU of vitamin D every other day or a placebo for eight weeks while continuing their stable regimen of dienogest. Pain severity was measured using the Visual Analog Scale and the Painful Endometriosis Symptoms questionnaire, while quality of life was assessed with the Endometriosis Health Profile-30.
Baseline demographic differences existed between groups, particularly in age, but body mass index was similar. The results showed that although there were slightly lower pain scores among those taking vitamin D, none of the between-group differences reached statistical significance for pain or quality of life outcomes. No serious adverse events occurred during the study; mild side effects such as nausea and fatigue were reported by some participants.
The authors suggested that background dienogest therapy may have suppressed symptoms before introducing vitamin D, potentially masking any additional benefit from supplementation. They also noted limitations such as not measuring post-intervention serum vitamin D levels and restricting participation to a small group from a single center.
The findings indicate that short-term adjunctive vitamin D does not offer statistically or clinically significant improvements in pain or quality of life among women already receiving dienogest therapy for endometriosis. The researchers recommend larger trials with longer follow-up periods and more comprehensive assessment strategies to further investigate potential benefits.
