Vitamin D Deficiency May Be a Modifiable Risk Factor in Women With Endometriosis

Objectives: This study aimed to determine the levels of 25(OH) D in endometriosis patients and to clarify the association between the endometriosis and dietary intake of calcium and vitamin D. Materials and Methods: A total of 200 women with endometriosis as endometriosis group and 154 healthy women (control group) of reproductive age were included in this study. The plasma 25(OH) D (vitamin D3) level was measured by high-pressure liquid chromatography method in endometriosis and control (healthy) groups. Participants in these 2 groups were asked about the dietary intake of calcium and vitamin D. Results: Our result showed the association between 25(OH) D deficiency and endometriosis risk (odds ratio [OR] = 29.4, P < 0.001). The intake of dietary calcium was also inversely associated with recurrence of endometriosis. However, this association was not observed between vitamin D intake and endometriosis. Conclusions: Our results showed that the decreased level of vitamin D (VD) is associated with the endometriosis risk. Accordingly, the authors validate that vitamin D deficiency may be regarded as a predisposing factor for endometriosis. In addition, a decreased risk of endometriosis with increasing calcium (Ca) intake was observed. Therefore, using Ca as dietary supplementation may be useful in the management of endometriosis in patients.