This study forthe first time presented that M. arvensis hydroalcoholic extractconsiderably decreased the expression of Cyp17 in PCOS rats.Increasing Cyp17 production increases androgen production.Subsequently, misplaced androgen production plays a pivotal role in the PCOSetiology (Rosenfield & Ehrmann, 2016).Hence, reduction of PCOS symptoms in treated rats with M. arvensisextract can be due to the influence of this plant on downregulation of theCyp17 expression and subsequently, reduction of androgenproduction. The gene discussed is CYP17A1; the disease is polycystic ovary syndrome.