title: Risk of multiple gestation after ovulation induction in polycystic ovary syndrome.
abstract: OBJECTIVE
  To compare the incidence of multiple gestation following treatment with clomiphene citrate (CC), metformin (MET) or gonadotropins in polycystic ovary syndrome (PCOS) patients undergoing ovulation induction.
  
  
  METHODS
  This was a retrospective, cohort study performed in an academic reproductive endocrine practice. PCOS patients presenting for first-trimester ultrasound were identified and assigned to 1 of 3 groups: CC-resistant patients who conceived after use of metformin +/- CC (group A), CC-resistant patients who conceived after gonadotropins (group B) and PCOS patients who conceived with CC only (group C). Multiple pregnancy outcome data were collected by chart review and patient interview.
  
  
  RESULTS
  One hundred one pregnancies were identified in PCOS patients who had conceived after ovulation induction (OI). The rate of multiple gestation was higher in group B (36%) than in A (0%) or C (11%).
  
  
  CONCLUSIONS
  The rate of multiple births was significantly lower with MET use during OI. Because multiple gestation is associated with higher complication rates and medical costs, our data offer an additional reason for use of MET for OI in PCOS patients who fail CC.
authors.affiliation: Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, Missouri, USA. rattsv@wustl.edu
authors.forename: Valerie S
authors.initials: VS
authors.lastname: Ratts
authors.forename: Rachel N
authors.initials: RN
authors.lastname: Pauls
authors.forename: Anil B
authors.initials: AB
authors.lastname: Pinto
authors.forename: Aldi
authors.initials: A
authors.lastname: Kraja
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Williams
authors.forename: Randall R
authors.initials: RR
authors.lastname: Odem
mesh_terms: D000328:Adult; D002996:Clomiphene / Q000627:therapeutic use; D005260:Female; D005300:Fertility Agents, Female / Q000627:therapeutic use*; D006062:Gonadotropins / Q000627:therapeutic use; D006801:Humans; D007247:Infertility, Female / Q000188:drug therapy* / Q000209:etiology; D008687:Metformin / Q000627:therapeutic use; D010062:Ovulation Induction / Q000009:adverse effects*; D011085:Polycystic Ovary Syndrome / Q000150:complications*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011272:Pregnancy, Multiple; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D005300:Fertility Agents, Female; D006062:Gonadotropins; D002996:Clomiphene; D008687:Metformin