IGF1 and polycystic ovary syndrome: To our best knowledge, this is the first randomized, single-blind, placebo-controlled interventional study that investigates the effect of calcium and vitamin D supplements as an adjuvant therapy to metformin on menstrual cycle abnormalities, gonadotropins, and IGF-1 system in vitamin D-deficient/insufficient PCOS women as the latter issue has never been addressed before.