title: Extra- and intra-ovarian factors in polycystic ovary syndrome: impact on oocyte maturation and embryo developmental competence.
abstract: BACKGROUND
  Polycystic ovary syndrome (PCOS) is a common metabolic dysfunction and heterogeneous endocrine disorder in women of reproductive age. Although patients with PCOS are typically characterized by increased numbers of oocytes retrieved during IVF, they are often of poor quality, leading to lower fertilization, cleavage and implantation rates, and a higher miscarriage rate.
  
  
  METHODS
  For this review, we searched the database MEDLINE (1950 to January 2010) and Google for all full texts and/or abstract articles published in English with content related to oocyte maturation and embryo developmental competence.
  
  
  RESULTS
  The search showed that alteration of many factors may directly or indirectly impair the competence of maturating oocytes through endocrine and local paracrine/autocrine actions, resulting in a lower pregnancy rate in patients with PCOS. The extra-ovarian factors identified included gonadotrophins, hyperandrogenemia and hyperinsulinemia, although intra-ovarian factors included members of the epidermal, fibroblast, insulin-like and neurotrophin families of growth factors, as well as the cytokines.
  
  
  CONCLUSIONS
  Any abnormality in the extra- and/or intra-ovarian factors may negatively affect the granulosa cell-oocyte interaction, oocyte maturation and potential embryonic developmental competence, contributing to unsuccessful outcomes for patients with PCOS who are undergoing assisted reproduction.
authors.affiliation: Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100083, People's Republic of China. jie.qiao@263.net
authors.forename: Jie
authors.initials: J
authors.lastname: Qiao
authors.forename: Huai L
authors.initials: HL
authors.lastname: Feng
mesh_terms: D047108:Embryonic Development; D005260:Female; D005640:Follicle Stimulating Hormone / Q000172:deficiency; D006801:Humans; D017588:Hyperandrogenism / Q000150:complications; D006946:Hyperinsulinism / Q000150:complications; D036341:Intercellular Signaling Peptides and Proteins / Q000502:physiology; D007986:Luteinizing Hormone / Q000378:metabolism; D009865:Oocytes / Q000254:growth & development* / Q000378:metabolism; D010053:Ovary / Q000503:physiopathology*; D019899:Paracrine Communication; D011085:Polycystic Ovary Syndrome / Q000150:complications / Q000196:embryology* / Q000378:metabolism; D011247:Pregnancy
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone