Author(s): Paliga Marta (ABDEF), Horák Stanis?aw (D)
The conventional mechanism of vitamin D bioactivity involves its impact on calcium–phosphate metabolism. Homeostasis in the levels of these two elements warrants undisturbed functioning of the nervous system and normal mineral bone density. Results of numerous investigations have confirmed that vitamin D affects reproductive processes in both males and females. The fact that the number of pregnancies, also those after IVF, is strictly correlated with a season of the year supports this claim. Also, high-latitude countries are characterized by lower ovulation parameters and higher incidence of endometriosis. Moreover, the concentration of calcitriol impacts the clinical course of polycystic ovary syndrome and the development of gestational diseases, i.e. gestational diabetes mellitus or pre-eclampsia. Moreover, an appropriate level of vitamin D has an influence of the regulation of the respiratory system: regular cycles and oocyte maturation. By reinforcing the action of gonadotropin, a hormone that regulates ovarian function, vitamin D3 has a direct effect on enhancing fertility.