New scientific data elucidate an increased rate of  of vitamin D deficiency worldwide, which has a negative impact both on the general health , as well as in each individual system, particularly the reproductive one. Α recent publication during the decade 1994-2004 in the US revealed that vitamin D’s deficiency has doubled.

The role of vitamin D in the bone protection is known and widely spread. However, cell receptors for the vitamin D are found in both bone cells as well as in many other cells and tissues of the organism. Vitamin D has the ability to bind to these receptors and affect cell function by activating or deactivating specific functions. Vitamin D deficiency has been linked to diabetes mellitus, obesity, the development of autoimmune and cardiovascular diseases, even cancer. Finally, mortality rates are directly related to the vitamin D levels in the blood.

Especially in the reproductive sector, research data, highlighting the importance of vitamin D in the proper functioning of the reproductive system, are multiplying.

Vitamin D receptors are found both in the ovary, the uterus and the placenta during pregnancy. It has been shown that from the beginning of the implantation process of the fertilized ovum, the endometrium synthesizes vitamin D to facilitate pregnancy and placental development. Moreover, vitamin D allows the womb’s immune cells to function effectively and to protect it from possible infections.

Data on the effects of vitamin D deficiency in the reproductive sector derive both from experimental studies, as well as from recorded complications during pregnancy. Specifically, during experimental studies in mice with congenital lack of vitamin D, hypoplasia of the matrix was observed, maturation disorder of the ova and generally an increased difficulty to conceive.

Correspondingly, data deriving from studies on high risk pregnancies due to vitamin D deficiency, show an increase in hypertension incidences during pregnancy and diabetes mellitus outbreak.

Particularly interesting is the role of Vitamin D in an IVF treatment. Data from several studies confirm negative correlation between vitamin D deficiency and the possibility of pregnancy after the embryo transfer.

Similar results were observed in egg donation fertility programs, indicating that the benefits of vitamin D occur mainly in the endometrial level. However, there are still no data to confirm the benefit of vitamin D supplementation in women undergoing IVF treatments, whereas before we adopt such an approach, we need to assure the supplements’ safety in the fertilization process, taking into account the duration of the therapy, the dosage and the way of administration.

Therefore, the additional use of vitamin D supplements is no panacea and their use has to be documented in each individual case with relevant diagnostic tests carried out by the experienced scientific staff of the assisted reproduction unit.