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.