Clinical and Experimental Reproductive Medicine

The Korean Society for Reproductive Medicine (대한생식의학회)
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The Efficacy of Letrozole in Women with a Poor Endometrial Response to Clomiphene Citrate

클로미펜에 불량한 자궁내막 발달을 보이는 여성에서 레트로졸의 유용성

  • Jang, Eun-Jeong (Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital) ;
  • Jee, Byung-Chul (Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital)
  • 장은정 (분당서울대학교병원 산부인과) ;
  • 지병철 (분당서울대학교병원 산부인과)
  • Published : 2010.03.31
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Abstract

Objective: To examine the efficacy of letrozole in infertile women showing a poor endometrial development at previous ovulation induction cycle by using clomiphene citrate. Methods: Eighteen infertile women were selected who showed a poor endometrial development (endometrial thickness$\leq$6.5 mm) after clomiphene treatment (50~100 mg) as ovulation induction for timed coitus. The mean age of the patients was $30.7{\pm}2.8$ years old and the mean duration of infertility was $33.1{\pm}26.6$ months. The infertility factors were identified as corrected endometriosis (n=1), polycystic ovary syndrome (n=5) and unexplained (n=12). Letrozole was given orally in a dose of 2.5 mg for 5 days starting 3~5 of menstrual cycle. Results: The number of follicles was significantly lower in the letrozole cycle when compared with previous clomiphene cycle ($1.1{\pm}0.3$ vs. $2.2{\pm}1.5$, p=0.011). The endometrial thickness (mm) at the time of triggering or LH surge was significantly greater in the letrozole cycle ($8.4{\pm}1.7$ vs. $5.8{\pm}0.5$, p<0.001). The endometrial pattern 'type C' was significantly higher in the letrozole cycle (94.4% vs. 50%, p=0.036). The pregnancy was achieved in 11.1% of the letrozole cycle. Conclusion: Use of letrozole was associated with more thick and improved endometrium than previous clomiphene cycles in which thin endometrium was identified. Use of letrozole appears to be an effective strategy for second-line treatment in women with inadequate endometrial response to clomiphene.

목 적: 클로미펜을 이용한 배란유도 주기에서 불량한 자궁내막 발달을 보이는 불임 여성에서 레트로졸의 효용성을 알아보고자 하였다. 연구방법: 2004년 3월부터 2009년 8월까지 분당서울대학교병원에서 클로미펜을 이용한 배란유도 주기에서 자궁내막 두께가 6.5 mm 이하여서 다음 주기에 레트로졸을 사용하였던 18명의 불임 여성을 선정하였다. 환자들의 평균 연령은 $30.7{\pm}2.8$세, 불임 기간은 $33.1{\pm}26.6$개월이었다. 불임의 인자는 자궁내막증이 1명, 다낭성난소증후군이 5명, 원인불명의 불임증이 12명이었다. 레트로졸은 2.5 mg의 용량으로 월경 3~5일 사이에 시작하여 5일간 투여하였다. 결 과: 이전 클로미펜 사용시와 비교하였을 때 레트로졸 주기에서 우성난포의 개수는 더 적었으나 ($1.1{\pm}0.3$ vs. $2.2{\pm}1.5$, p=0.011) 자궁내막 두께는 유의하게 증가하였으며 ($8.4{\pm}1.7$ mm vs. $5.8{\pm}0.5$ mm, p<0.001) 자궁내막 패턴 중 type C의 빈도는 이전 클로미펜 주기에서 50%이었던 것이 레트로졸 사용시 94.4%로 유의한 증가를 보였다 (p=0.036). 레트로졸을 이용한 배란 유도 주기에서 임신율은 11.1%였다. 결 론: 얇은 자궁내막 발달을 보였던 클로미펜 주기에 비해 레트로졸 사용시 자궁내막이 좀 더 두꺼워지고 패턴이 호전되는 것으로 보아 클로미펜에 불량한 자궁내막을 보이는 여성에서 이차 선택약제로 레트로졸의 사용은 유용한 방법으로 사료된다.

Keywords

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