Effects of preconceptional vitamin D levels on in vitro fertilization outcomes in infertile patients with polycystic ovary syndrome: A retrospective cohort study.

Background: Vitamin D plays various roles in different stages of reproduction, and abnormalities in its levels are associated with diseases such as polycystic ovary syndrome (PCOS). This study aimed to determine the relationship between initial vitamin D levels and in vitro fertilization (IVF) outcomes in PCOS patients.

Methods: This retrospective cohort study included 1174 PCOS patients who consulted the Acıbadem Maslak Hospital IVF Clinic between January 2015 and March 2021.