title: The use of metformin for women with PCOS undergoing IVF treatment.
abstract: BACKGROUND
  Metformin appears to improve reproductive function in some women with polycystic ovary syndrome (PCOS). We wished to explore the effect of metformin in women with PCOS undergoing IVF.
  
  
  METHODS
  A randomized, placebo-controlled, double-blind study was carried out between 2001 and 2004. Patients with PCOS undergoing IVF/ICSI treatment using a long GnRH agonist protocol were randomized to receive metformin (MET), 850 mg, or placebo (PLA) tablets twice daily from the start of the down-regulation process until the day of oocyte collection. The primary outcome was to be an improvement in the overall fertilization rate.
  
  
  RESULTS
  One-hundred and one IVF/ICSI cycles were randomized to receive metformin (52) or to receive placebo (49). There was no difference in the total dose of rFSH required per cycle (median dose: MET = 1200 U, PLA = 1300 U; P = 0.937). The median number of oocytes retrieved per cycle (MET = 17.2, PLA = 16.2; P = 0.459) and the overall fertilization rates (MET = 52.9%, PLA = 54.9%; P = 0.641) did not differ. However, both the clinical pregnancy rates beyond 12 weeks gestation per cycle (MET = 38.5%, PLA = 16.3%; P = 0.023) and per embryo transfer (MET = 44.4%, PLA = 19.1%; P = 0.022) were significantly higher in those treated with metformin. Furthermore, a significant decrease in the incidence of severe ovarian hyperstimulation syndrome (OHSS) was observed (MET = 3.8%, PLA = 20.4%; P = 0.023), and this was still significant after adjustment for BMI, total rFSH dose and age (OR = 0.15; 95% CI: 0.03, 0.76; P = 0.022).
  
  
  CONCLUSIONS
  Short-term co-treatment with metformin for patients with PCOS undergoing IVF/ICSI cycles does not improve the response to stimulation but significantly improves the pregnancy outcome and reduces the risk of OHSS.
authors.affiliation: Department of Reproductive Medicine, The General Infirmary, Leeds, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Tang
authors.forename: Julie
authors.initials: J
authors.lastname: Glanville
authors.forename: Nic
authors.initials: N
authors.lastname: Orsi
authors.forename: Julian H
authors.initials: JH
authors.lastname: Barth
authors.forename: Adam H
authors.initials: AH
authors.lastname: Balen
mesh_terms: D000328:Adult; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D005640:Follicle Stimulating Hormone / Q000627:therapeutic use; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D008687:Metformin / Q000627:therapeutic use*; D016017:Odds Ratio; D010919:Placebos; D011085:Polycystic Ovary Syndrome / Q000188:drug therapy*; D011247:Pregnancy; D018873:Pregnancy Rate; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D007004:Hypoglycemic Agents; D010919:Placebos; D007987:Gonadotropin-Releasing Hormone; D005640:Follicle Stimulating Hormone; D008687:Metformin