title: Is the addition of metformin efficacious in the treatment of clomiphene citrate-resistant patients with polycystic ovary syndrome? A structured literature review.
abstract: OBJECTIVE
  The aim of this literature search is to establish if metformin is efficacious when given to clomiphene citrate (CC)-resistant polycystic ovary syndrome (PCOS) patients.
  
  
  METHODS
  Medline database was searched from 1 January 1980 to 1 January 2005. Inclusion criteria were prospective randomized control trials where metformin was randomized either with placebo or CC to induce ovulation in the CC-resistant patient.
  
  
  RESULTS
  Group 1: Four trials were prospective double-blind placebo controlled. When the data of the four trials were pooled, the overall effect of the addition of metformin in the CC patient was P=.0006 with a 95% confidence interval (CI) of odds ratio (OR) 1.81-8.84. Group 2: In two trials the randomization was only prospective. When the data of these two trials were pooled, the overall effect of the addition of metformin in the CC-resistant patient was P<.0001 with a 95% CI of OR 6.24-70.27. Groups 1 and 2: The combined data show an overall effect of P<.0001 with a 95% CI of OR 3.59-12.96.
  
  
  CONCLUSIONS
  The addition of metformin in the CC-resistant patient is highly effective in achieving ovulation induction.
authors.affiliation: Reproductive Biology Unit, Department of Obstetrics and Gynaecology, Stellenbosch University and Tygerberg Hospital, Tygerberg, South Africa. mtis@xsinet.co.za
authors.forename: Thomas I
authors.initials: TI
authors.lastname: Siebert
authors.forename: Thinus F
authors.initials: TF
authors.lastname: Kruger
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Steyn
authors.forename: Saleema
authors.initials: S
authors.lastname: Nosarka
mesh_terms: D002996:Clomiphene / Q000008:administration & dosage*; D004338:Drug Combinations; D004351:Drug Resistance; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage; D006801:Humans; D007247:Infertility, Female / Q000188:drug therapy* / Q000209:etiology; D016239:MEDLINE; D008687:Metformin / Q000008:administration & dosage*; D010060:Ovulation / Q000187:drug effects*; D010062:Ovulation Induction / Q000379:methods*; D011085:Polycystic Ovary Syndrome / Q000150:complications / Q000188:drug therapy*; D011247:Pregnancy; D011256:Pregnancy Outcome; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome
chemical_list: D004338:Drug Combinations; D005300:Fertility Agents, Female; D002996:Clomiphene; D008687:Metformin