Letrozole as the first-line treatment of infertile women with poly cystic ovarian syndrome (PCOS) compared with clomiphene citrate: A clinical trial

Authors

Department of Gynecology and Obstetrics, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Background: The purpose of this study was to determine the efficacy and safety of letrozole on ovulation induction and pregnancy in comparison with clomiphene citrate in PCOS patients.
Materials and Methods: The study was based on prospective randomized clinical trial comparing the efficacy of letrozole as the first-line management of the PCOS patients in comparison to clomiphene citrate during 2009 to 2011 and was performed in one private infertility clinic. The study included 100 patients divided into 2 equal groups.
Results: Pregnancy occurred in 29 of 50 patients in letrozole group (58%) and 24 of 51 patients in clomiphene group (47%). The difference was not statistically significant (P value = 0.23). Thirty patients in clomiphene group and 36 patients in letrozole group showed regular menses after or during the treatment course. No significant difference between the 2 groups was observed (P value = 0.21).
Conclusion: Our findings suggest letrozole and clomiphene citrate are equally effective for induction of ovulation and achieving pregnancy in patients with PCOS.

Keywords

1.
Azziz R, Woods KS, Reyna R, Key TJ, Knochenhauer ES, Yildiz BO. The prevalence and features of the polycystic ovary syndrome in an unselected population. J Clin Endocrinol Metab 2004;89:2745-9.   Back to cited text no. 1
    
2.
King J. Polycystic ovary syndrome. J Midwifery Womens Health 2006;51:415-22.  Back to cited text no. 2
    
3.
Revised 2003 consensus on diagnostic criteria and long-term health risks related to polycystic ovary syndrome (PCOS). Hum Reprod 2004;19:41.  Back to cited text no. 3
    
4.
Misso ML, Wong JL, Teede HJ, Hart R, Rombauts L, Melder AM, et al. Aromatase inhibitors for PCOS: A systematic review and meta-analysis. Hum Reprod Update 2012;18:301-12.  Back to cited text no. 4
    
5.
Badawy A, Abdel Aal I, Abulatta M. Anastrozole or letrozole for ovulation induction in clomiphene resistant women with polycystic ovarian syndrome: A prospective randomized trial. Fertil Steril 2008;89:1209-12.  Back to cited text no. 5
    
6.
Mitwally FM, Casper RF. Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate. Fertil Steril 2001;75:305-9.  Back to cited text no. 6
    
7.
Al-Omari WR, Sulaiman W, Al-Hadithi N. Comparison of two aromatase inhibitors in women with clomiphene- resistant polycystic ovary syndrome. Int J Gynecol Obstet 2004;85:289-91.  Back to cited text no. 7
    
8.
Elnashar A, Fouad H, Eldosoky M, Saeid N. Letrozole induction of ovulation in women with clomiphene citrate resistant polycystic ovary syndrome may not depend on the period of infertility, the body mass index, or the luteinizing hormone/follicle- stimulating hormone ratio. Fertil Steril 2006;85:511-3.  Back to cited text no. 8
    
9.
Badawy A, Elnashar A, Totongy M. Clomiphene citrate or aromatase inhibitors for superovulation in women with unexplained infertility undergoing intrauterine insemination: A prospective randomized trial. Fertil Steril 2009;92:1355-9.  Back to cited text no. 9
    
10.
Mahani IM, Afnan M. The pregnancy rates with intrauterine insemination (IUI) in superovulated cycles employing different protocols (clomiphen citrate (CC), human menopausal gonadotropin (HMG) and HMG+CC) and in natural ovulatory cycle. J Pak Med Assoc 2004;54:503-5.   Back to cited text no. 10
    
11.
Eden JA, Place J, Carter GD, Jones J, Alaghband-Zadeh J, Pawson ME. The effect of clomiphene citrate on follicular phase increase in endometrial thickness and uterine volume. Obstet Gynecol 1989;73:187-90.   Back to cited text no. 11
    
12.
Randall JM, Templeton A. Transvaginal sonographic assessment of follicular and endometrial growth in spontaneous and clomiphene citrate cycles. Fertil Steril 1991;56:208-12.  Back to cited text no. 12
    
13.
Sgarlata CS, Mikhail G, Hertelendy F. Clomiphene and tamoxifen inhibit progesterone synthesis in granulosa cells: Comparison with estradiol. Endocrinology 1984;114:2032-8.  Back to cited text no. 13
    
14.
Niswender GD, Davis TL, Griffith RJ, Bogan RL, Monser K, Bott RC, et al. Judge, jury and executioner: The auto-regulation of luteal function. Soc Reprod Fertil Suppl 2007;64:191-206.  Back to cited text no. 14
    
15.
Olsson JH, Nilsson L, Hillensjo T. Effect of clomiphene isomers on progestin synthesis in cultured human granulosa cells. Hum Reprod 1987;2:463-8.  Back to cited text no. 15
    
16.
Schmidt GE, Kim MH, Mansour R, Torello L, Friedman CI. The effects of enclomiphene and zuclomiphene citrates on mouse embryos fertilized in vitro and in vivo. Am J Obstet Gynecol 1986;154:727-36.  Back to cited text no. 16
    
17.
Young SL, Opsahl MS, Fritz MA. Serum concentrations of enclomiphene and zuclomiphene across consecutive cycles of clomiphene citrate therapy in anovulatory infertile women. Fertil Steril 1999;71:639-44.  Back to cited text no. 17