A similar relationship was observed between vitamin D status and the fertilization rates (P<0.001) after adjusting for potential confounders (age, BMI, AMH, type of infertility, previous pregnancy, seasons when sample were taken, the type of treatment protocol, duration of stimulation, E2 levels on the day of hCG, number of larger follicles, number of oocytes retrieved and number of mature oocytes). The gene discussed is AMH; the disease is Infertility.