Clinical research on the relative efficacy of letrozole and clomiphene citrate in achieving ovulation among women with polycystic ovarian syndrome
DOI:
https://doi.org/10.18203/2320-1770.ijrcog20261158Keywords:
PCOS, Infertility, Letrozole, Clomiphene citrate, Ovulation inductionAbstract
Background: Polycystic ovarian syndrome (PCOS) is a leading cause of anovulatory infertility. PCOS is the most common cause of infrequent periods (oligomenorrhoea) and absence of periods (amenorrhoea). It affects about 4% to 8% of women worldwide and often leads to anovulatory subfertility. Clomiphene citrate (CC) has been widely used for ovulation induction but is limited by endometrial effects and resistance. Letrozole, an aromatase inhibitor, has emerged as an alternative with potentially superior efficacy. Aim of the study was to compare the efficacy of letrozole and CC in ovulation induction among women with PCOS.
Methods: A prospective comparative study was conducted on 100 infertile women with PCOS aged 21–35 years at Government Peripheral Hospital, Tondiarpet, Chennai, from September 2024 to August 2025. Participants were allocated into two groups: letrozole (n=50) and clomiphene citrate (n=50). Follicular development and rupture were assessed by transvaginal ultrasonography. Statistical analysis was performed using statistical package for the social sciences (SPSS), with p<0.05 considered significant.
Results: The mean age was 26.3±2.5 years. The mean follicle number was lower in the letrozole group (1.5±0.89) compared with clomiphene (2.54±1.69). The mean number of ruptured follicles was significantly lower with letrozole (0.96±0.64) compared with clomiphene (1.48±1.07). Letrozole demonstrated a safer monofollicular response, while clomiphene induced multifollicular development.
Conclusions: Both agents are effective for ovulation induction. Letrozole offers a safer monofollicular profile with reduced risk of multiple gestations, making it preferable when minimizing multiple pregnancies is a priority.
References
Liu Z, Geng Y, Huang Y, Hu R, Li F, Song Y, et al. Letrozole Compared With Clomiphene Citrate for Polycystic Ovarian Syndrome: A Systematic Review and Meta-analysis. Obstet Gynecol. 2023;141(3):523-34.
Mitwally MF, Casper RF. Potential of aromatase inhibitors for ovulation and superovulation induction in infertile women. Drugs. 2006;66:2149-60.
Melo AS, Ferriani RA, Navarro PA. Treatment of infertility in women with polycystic ovary syndrome: approach to clinical practice. Clinics. 2015;70:765-9.
Kar S. Clomiphene citrate or letrozole as first-line ovulation induction drug in infertile PCOS women: a prospective randomized trial. J Hum Reprod Sci. 2012;5:262-5.
Sakar MN, Oglak SC. Letrozole is superior to clomiphene citrate in ovulation induction in patients with polycystic ovary syndrome. Pak J Med Sci. 2020;36:1460-5.
Teede HJ, Tay CT, Laven JJE, Dokras A, Moran LJ, Piltonen TT, et al. Recommendations From the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. J Clin Endocrinol Metab. 2023;108(10):2447-69.
Casper RF, Mitwally MF. Review: Aromatase inhibitors for ovulation induction. J Clin Endocrinol Metab. 2006;91:760-71.
Ganesh A, Goswami SK, Chattopadhyay R, Choudhury K, Chakravarty B. Comparison of letroz with continuous gonadotropins and clomiphene gonadotropin combination for ovulation induction. In 1387 PCOS women after clomiphene citrate failure: A randomized prospective clinical trial. J Assist Reprod Genet. 2009;26:19-24.
Pandit K, Goswami S, Ghosh S, Mukhopadhyay P, Chowdhury S. Insulin resistance in metabolic syndrome in Indian PCOS South Asians. Indian J Endocrinal Metab. 2012;16:44-55.
Hegde R, Maitra C. Comparison of the role of letrozole & clomiphene citrate as a first line ovulation induction drug in infertile women with polycystic ovary syndrome. Indian J Obstet Gynecol Res. 2020;7(1):12-5.
Al-Omari WR, Sulaiman WR, Al-Hadithi N. Comparison of two aromatase inhibitors in women with clomiphene-resistant polycystic ovary syndrome. Int J Gynaecol Obstet. 2004;85(3):289-91.
Hendawy S, Samaha H, Elkholy M. Letrozole versus clomiphene citrate for induction of ovulation in patients with polycystic ovarian syndrome undergoing intrauterine insemination. Clin Med Insights Reprod Health. 2011;5:11-6.
Mitwally M, Casper R. Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate. Fertil Steril. 2001;75:305-9.
Legro RS, Brzyski RG, Diamond MP, Coutifaris C, Schlaff WD, Casson P, et al. Letrozole versus clomiphene for infertility in the polycystic ovary syndrome. N Engl J Med. 2014;371:119-29.
Seyedoshohadaei F, Tangestani L, Zandvakili F, Rashadmanesh N. Comparison of the Effect of Clomiphene- Estradiol Valerate vs Letrozole on Endometrial Thickness, Abortion and Pregnancy Rate in Infertile Women with Polycystic Ovarian Syndrome. J Clin Diag Res. 2016;10(8):QC10.
Wang R, Li W, Bordewijk EM, Legro RS, Zhang H, Wu X, et al. First-line ovulation induction for polycystic ovary syndrome:an individual participant data meta-analysis. Hum Reprod Update. 2019;25:717-32.
Yun L. Clinical study on various doses of letrozole for ovulation induction in clomiphene-resistant patients with ploycystic ovary syndrome. Modern Med Health. 2008;24:3197-8.
Zargoon A, Toussy JA, Darbanan FF. Pregnancies following the use of sequential treatment of metformin and incremental doses of letrozole in clomiphen-resistant women with polycystic ovary syndrome. Iran J Reprod Med. 2012;10(1):33-40.
Gregorious O, Vlahos NF, Konidaris S, Papadias K, Botsis D, Creatsas GK. Randomized controlled trial comparing superovulation with letrozole versus recombinant follicle-stimulating hormone combined with intrauterine insemination for couples with unexplained infertility who had failed clomiphene citrate stimulation and intrauterine insemination. Fertil Steril. 2008;90:678-83.
Ryan GL, Moss V, Davis WA, Sparks AE, Dokras A, Van Voorhis BJ. Oral ovulation induction agents combined with low-dose gonadotrophin injections and intrauterine insemination: Cost and clinical effectiveness. J Reprod Med. 2005;50:943-50.
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