The menstrual cycle in PCOS

Abstract

Polycystic ovary syndrome (PCOS) is defined as a syndrome of ovarian dysfunction along with the cardinal features of hyperandrogenism and polycystic ovary morphology in the absence of other explanatory endocrinopathies [1]. The etiology of PCOS is multifactorial and complex with hyperinsulinemia, abnormal ovarian steroidogenesis, and neuroendocrine abnormalities playing significant interactive roles. The vast majority of patients have menstrual irregularities and recent studies have indicated that those with menstrual cycle dysfunction also tend to be more hyperandrogenic and hyperinsulinemic [2, 3]. This chapter will review the integration of ovarian, hypothalamic and pituitary factors that occur in normal menstrual cycles; will discuss the variable patterns of menstrual dysfunction in patient with PCOS; and will review what is known about the potential etiology of ovarian dysfunction in PCOS. © 2009 Springer-Verlag US.