1,25-Dihydroxyvitamin D3 has a direct effect on steroid production from human theca cells

Abstract

There is evidence from animal studies that 1,25-dihyroxyvitamin D3 (1,25(OH)2D3) is essential for normal reproductive function. Vitamin deficient rats have reduced fertility and VDR null mutant mice demonstrate impaired folliculogenesis. One small uncontrolled study in humans has demonstrated that vitamin D replacement improves menstrual frequency and acne in women with polycystic ovary syndrome (PCOS). We have previously demonstrated that 1,25(OH)2D3 inhibits the production of oestradiol independently of progesterone in luteinised but not in non-luteinised granulosa cells. We have also demonstrated the presence of vitamin D receptors on luteinised granulosa cells and cells of the corpus luteum