title: Time of initiation of clomiphene citrate and pregnancy rate in polycystic ovarian syndrome.
abstract: OBJECTIVE
  To investigate whether the timing of clomiphene citrate (CC) administration affects hormonal levels, follicular growth, endometrial thickness, and ovulation and pregnancy rates in women with polycystic ovarian syndrome (PCOS).
  
  
  METHODS
  Of the 78 infertile women with PCOS who participated in this prospective, double-blind, randomized clinical trial, 37 collectively underwent 71 cycles of CC (100 mg/day) on days 1 through 5 of the menstrual cycle (group 1) and 41 collectively underwent 73 cycles of CC at the same concentration on days 5 through 9 (group 2). Hormonal levels, follicular growth, endometrial thickness, and ovulation and pregnancy rates were compared.
  
  
  RESULTS
  The mean number of follicles and the maximum follicular size were greater in group 2. However, ovulation rates were 72.8% in group 1 and 70.8% in group 2 (P=.78), and pregnancy rates were 40.5% in group 1 and 19.5% in group 2 (P=.04).
  
  
  CONCLUSIONS
  Treatment with CC is associated with higher rates of pregnancy if started early (days 1-5) in the menstrual cycle.
authors.affiliation: Infertility research Center, Department of Obstetrics and Gynecology, Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: S
authors.initials: S
authors.lastname: Dehbashi
authors.forename: H
authors.initials: H
authors.lastname: Vafaei
authors.forename: M D
authors.initials: MD
authors.lastname: Parsanezhad
authors.forename: S
authors.initials: S
authors.lastname: Alborzi
mesh_terms: D000328:Adult; D002996:Clomiphene / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004717:Endometrium / Q000187:drug effects; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D043373:Follicle Stimulating Hormone, Human / Q000097:blood; D006801:Humans; D007247:Infertility, Female / Q000188:drug therapy* / Q000209:etiology; D007986:Luteinizing Hormone / Q000097:blood; D006080:Ovarian Follicle / Q000187:drug effects; D010060:Ovulation / Q000187:drug effects; D011085:Polycystic Ovary Syndrome / Q000150:complications / Q000188:drug therapy*; D011247:Pregnancy; D018873:Pregnancy Rate; D011374:Progesterone / Q000097:blood; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D005300:Fertility Agents, Female; D043373:Follicle Stimulating Hormone, Human; D002996:Clomiphene; D011374:Progesterone; D007986:Luteinizing Hormone