Uzma Afreen, Mubushra Samina, Shaima Sultana Memon, Hafiz Syed Muhammad Osama Jafri, Sumaira Riffat, Saba Abrar 2023. Relationship Between Serum 25-Hydroxy Vitamin D Level and Menstrual Cycle Irregularity: A Cross-Sectional Study. Pakistan Journal of Medical & Health Sciences. 16, 11 (Jan. 2023), 511. DOI:https://doi.org/10.53350/pjmhs20221611511.