title: Interference with uterine blood flow by clomiphene citrate in women with unexplained infertility.
abstract: OBJECTIVE
  To investigate the effect of clomiphene citrate on the uterine blood flow in women with unexplained infertility.
  
  
  METHODS
  Twenty-one women who had normal uterine blood flow (pulsatility index [PI] less than 3 from the LH peak to the middle luteal phase of a natural ovulatory cycle) were enrolled in this study. Patients were given clomiphene citrate (100 mg/day) from days 5-9 of the next ovulatory cycle. The PI values measured in the natural and clomiphene citrate-treated cycles were compared using repeated measures analysis of variance. Their correlations with the estradiol (E2) and progesterone concentrations in the treatment cycle were calculated using the Pearson correlation coefficient.
  
  
  RESULTS
  In the natural cycles of those with normal uterine blood flow, the highest impedance of uterine blood flow was detected at the late follicular phase, then blood flow increased during the luteal phase. In the clomiphene citrate-treated cycles, a statistically significant decrease in uterine blood flow also occurred during the early luteal phase (P < .05). No significant correlation of E2 or progesterone serum concentrations with PI values of the uterine artery could be found in either natural or clomiphene citrate-treated cycles.
  
  
  CONCLUSIONS
  The use of clomiphene citrate decreases the uterine blood flow during the early luteal phase, a periimplantation stage.
authors.affiliation: Department of Obstetrics and Gynecology, National Cheng Kung University Medical College, Tainan, Taiwan, Republic of China.
authors.forename: C C
authors.initials: CC
authors.lastname: Hsu
authors.forename: H C
authors.initials: HC
authors.lastname: Kuo
authors.forename: S T
authors.initials: ST
authors.lastname: Wang
authors.forename: K E
authors.initials: KE
authors.lastname: Huang
mesh_terms: D000328:Adult; D002996:Clomiphene / Q000494:pharmacology*; D004717:Endometrium / Q000473:pathology; D004958:Estradiol / Q000097:blood; D005260:Female; D005300:Fertility Agents, Female / Q000627:therapeutic use*; D006801:Humans; D007247:Infertility, Female / Q000097:blood / Q000503:physiopathology*; D007986:Luteinizing Hormone / Q000097:blood; D008597:Menstrual Cycle; D012039:Regional Blood Flow / Q000187:drug effects; D014599:Uterus / Q000098:blood supply*
chemical_list: D005300:Fertility Agents, Female; D002996:Clomiphene; D004958:Estradiol; D007986:Luteinizing Hormone