Vitamin D as a follicular marker of human oocyte quality and a serum marker of in vitro fertilization outcome.

This study reveals that the level of 25(OH)D in FF correlates negatively with the oocytes' ability to undergo fertilization and subsequent preimplantation embryo development. Oocytes matured in FF with low 25(OH)D concentration are more likely to produce top quality embryos and are associated with higher pregnancy and delivery rates. On the other hand, low serum vitamin D concentration is associated with higher miscarriage rates.