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What is Ovarian tumours commonly arises from: March 2005 and explain in detail?
Ans. A: Surface epithelium Ovarian tumor arises from one of the tree main components: Surface epithelium Germ cells Stroma of the ovary. Most primary neoplasm in the ovary is epithelial tumours. Factors that decrease the risk for ovarian cancer predominantly reduce the number of ovulation cycles a women encounter, such as the use of oral contraceptives, breast-feeding and multiparity. Long-term use of oral contraceptives has reduced the risk of ovarian cancer by more than 50% in unselected women. Decreased risk of ovarian cancer has also been associated with tubal ligation and hysterectomy.