title: Comparison of the Effect of Clomiphene- Estradiol Valerate vs Letrozole on Endometrial Thickness, Abortion and Pregnancy Rate in Infertile Women with Polycystic Ovarian Syndrome.
abstract: BACKGROUND
  Clomiphene citrate is the first-line therapy for ovulation induction in Polycystic Ovarian Syndrome (PCOS). This drug binds and blocks estrogen receptors and thought to have an anti estrogenic effect on endometrium volume, thus may have adverse effect on fertility.
  
  
  OBJECTIVE
  This study aimed to compare the effect of Clomiphene citrate plus Estradiol Valerate with Letrozole on endometrial thickness, abortion and pregnancy rate in infertile women with PCOS undergoing ovulation induction.
  
  
  METHODS
  This was a randomized double blind clinical trial study on 100 women with PCOS, with an endometrial thickness less than 7mm in spite of follicles greater than 18mm after administration of Clomiphene citrate 100mg/d from 3(th) to 7(th) day of menstruation. They were randomly divided in two groups. Group A received 100mg Clomiphene citrate from day 3 to day 7 of menstruation and 4 mg Estradiol Valerate after the 8(th) day of menstruation until 14(th) day. Group B treated by 5mg Letrozole from day 3 to 7 of menstruation with placebo from 8(th) to 14(th) day of menstruation. In both groups endometrial thickness was measured by transvaginal sonography in the 14(th) day of menstruation. Data were analysed using SPSS Ver.18.0.
  
  
  RESULTS
  The mean age was 30.34 years in group A and 29.62 years in group B (p=0.381). The number of infertility years in group A was 3.73 years and in group B was 3.85 years. There was no significant relationship statistically between the two groups in terms of mean age and infertility years (p=0.99). Endometrial thickness in group A was 7.26mm and in group B was 8.17 mm. Pregnancy rates in group A and group B was 32% and 16% respectively. There was significant relationship statistically between the two groups in terms of endometrial thickness and pregnancy rates (p=0.021 and p=0.05). There was no abortion in group A and 5 cases had abortion in group B, there was a significant relationship between the two groups statistically (p=0.028).
  
  
  CONCLUSIONS
  Letrozole increased endometrial thickness and pregnancy rate in infertile women, therefore its administration is recommended.
authors.affiliation: Associate Professor, Department of Obstetrics and Gynecology, Faculty of Medicine, Kurdistan University of Medical Sciences , Sanandaj, Iran .
authors.forename: Fariba
authors.initials: F
authors.lastname: Seyedoshohadaei
authors.affiliation: Resident, Department of Obstetrics and Gynecology, Faculty of Medicine, Kurdistan University of Medical Sciences , Sanandaj, Iran .
authors.forename: Laleh
authors.initials: L
authors.lastname: Tangestani
authors.affiliation: Assistant Professor, Department of Obstetrics and Gynecology, Faculty of Medicine, Kurdistan University of Medical Sciences , Sanandaj, Iran .
authors.forename: Farnaz
authors.initials: F
authors.lastname: Zandvakili
authors.affiliation: Lecturer, Research Center for Gastroenterology and Hepatology, Faculty of Medicine, Kurdistan University of Medical Sciences , Sanandaj, Iran .
authors.forename: Naser
authors.initials: N
authors.lastname: Rashadmanesh
keywords: Drug therapy; Female; Infertility