A comparison of the effects of clomiphene citrate and the aromatase inhibitor letrozole on superovulation in Asian women with normal ovulatory cycles

Objective. To compare the effect of the aromatase inhibitor letrozole and clomiphene citrate (CC) on superovulation in women with normal ovulation.

Methods. A cross-over randomized study of 22 women with normal ovulation, divided randomly into two equal cohorts, was carried out. Each group of 11 women was randomly allocated to take letrozole or CC for one cycle. After washing out for one cycle, the alternative drug was administered in the subsequent cycle. The number and size of mature follicles, endometrial thickness, and estradiol and progesterone levels were monitored.

Results. The number of mature follicles and estradiol levels on ovulation day were significantly lower in the letrozole group than the CC group (p < 0.05 for both). However, no differences between the two groups in endometrial thickness and pattern were observed. Progesterone levels showed ovulation in all cycles.

Conclusions. The administration of 50 mg CC on days 3–5 was superior to 2.5 mg letrozole for superovulation induction in women with normal ovulation.     

Comparison of clomiphene citrate and letrozole for ovulation induction in women with polycystic ovary syndrome: a prospective randomized trial

To compare the therapeutic efficacy of clomiphene citrate (CC) and letrozole (LE) on ovulation, pregnancy, and live birth in women with polycystic ovary syndrome (PCOS); and to ensure if LE can replace CC as the first-line therapy for ovulation induction in these women. This is a prospectively, randomized, controlled trial in the tertiary hospital. Two-hundred and sixty-eight anovulatory PCOS patients were treated by CC or CC plus metformin and LE or LE plus metformin for three continuous cycles or conception; their ovulation rates, pregnancy rates, and live birth rates were calculated and compared. No significant difference was noted among the four groups regarding to the baseline data of clinical manifestations, serum sex hormone levels, and serum insulin levels. A total of 240 patients completed the therapies. The ovulation rate was significantly higher in the group LE than the group CC; however, no significant difference was noted between the groups LE and CC, CC, and CC?+?MET, or LE and LE?+?MET in the pregnancy rate, abortion rate, and live birth rate. No birth defect was found in the total of 63 newborns. CC regimen was still recommended to be the first-line therapy of ovulation induction for PCOS.     

A randomized double-blind comparison of the effects of clomiphene citrate and the aromatase inhibitor letrozole on ovulatory function in normal women

OBJECTIVE: To evaluate the ovarian follicular dynamics of cycle modification with the aromatase inhibitor letrozole compared with clomiphene citrate in normal ovulatory women. DESIGN: Randomized double-blind controlled trial. SETTING: Tertiary care hospital. PATIENT(S): Nineteen ovulatory female volunteers, ages 18-35 years. INTERVENTION(S): Subjects were monitored in one control cycle. Subjects then received either letrozole 2.5 mg daily or clomiphene citrate 50 mg daily on days 5-9 after menses. MAIN OUTCOME MEASURE(S): Number of mature follicles, endometrial thickness and endometrial pattern at ovulation, and follicular profiles of LH, FSH, and E(2). RESULT(S): The number of mature follicles at the LH surge in natural cycles was 1.0 with an exaggerated response seen for treatment both with clomiphene and letrozole. There was no difference in the endometrial thickness at midcycle during either the natural cycles or the medicated cycles. LH surges and spontaneous ovulation were documented in all natural and medicated cycles. When measured daily, follicular profiles of LH and FSH are similar between the groups in both the natural and medicated cycles. In the medicated cycles, clomiphene results in a significant increase in E(2) levels, while E(2) levels in letrozole-stimulated cycles appeared lower than in natural cycles. CONCLUSION(S): Transient inhibition of aromatase activity in the early follicular phase with the aromatase inhibitor letrozole results in stimulation of ovarian folliculogenesis similar to that seen with clomiphene citrate with no apparent adverse effect on endometrial thickness or pattern at midcycle.     

Clomiphene citrate combined with metformin versus letrozole for induction of ovulation in clomiphene-resistant polycystic ovary syndrome: a randomized clinical trial

A total of 202 patients with clomiphene citrate (CC) -resistant polycystic ovary syndrome (PCOS) were randomly allocated into two arms of induction of ovulation; the first group (n?=?102) received CC 100?mg and metformin 500?mg while the second group (n?=?100) received letrozole 2.5?mg with ovulation rate, clinical pregnancy rate, adverse effects, and acceptability were assessed. Patients in the letrozole arm experienced higher rate of ovulation (82% versus 43.1%, p?p?p?p?p?p?p?相似文献   

Comparison of endometrial receptivity of clomiphene citrate versus letrozole in women with polycystic ovary syndrome: a randomized controlled study

Abstract

The aim of the study was to compare the effect of clomiphene citrate (CC) and letrozole on endometrial receptivity for ovulation induction in women with polycystic ovary syndrome (PCOS). A randomized controlled study included 160 patients diagnosed with PCOS, out of which 80 patients received 50?mg of CC and 80 patients received 2.5?mg of letrozole for successful ovulation induction. Endometrial thickness and pattern, the blood flow of uterine artery and subendometrial region, endometrial volume and vascularization index were measured. The ratio of multilayered endometrial pattern in letrozole group was significantly increased on the day of human chorionic gonadotropin (hCG) administration compared with CC group (77.5% vs. 55.0%). The volume, vascularization index (VI), flow index (FI), and vascularization flow index (VFI) of endometrium on the day of hCG administration and 7–9?days after ovulation in letrozole group were significantly increased. The biochemical pregnancy rate, clinical pregnancy rate, and ongoing pregnancy rate in letrozole group were significantly increased compared with CC group (36.3%, 30.0%, 22.5% vs. 21.3%, 13.8%, 10.0%, respectively). Letrozole increased pregnancy rates by improving endometrial receptivity compared with CC in patients with PCOS.     

Cost effectiveness of letrozole and purified urinary FSH in treating women with clomiphene citrate-resistant polycystic ovarian syndrome: a randomized controlled trial

We aimed to compare the cost effectiveness of letrozole versus purified urinary follicle stimulating hormone (FSH) in treating patients with clomiphene citrate (CC)-resistant polycystic ovary syndrome (PCOS). This was a randomized trial conducted in Cairo University and Beni-Suef University Hospitals, Egypt. A cohort of 140 eligible women was randomized to receive either letrozole 2.5?mg twice daily for five days, or FSH using a graduated regimen starting with a dose of 75?IU. Treatment was repeated for three months if pregnancy did not occur. There were no significant differences between the two treatments in the cumulative clinical pregnancy rate (30% vs. 34%; p?=?0.578), cumulative ovulation rate (47% vs. 57%; p?=?0.236), miscarriage rate (9% vs. 4%, p?>?0.999) or multiple pregnancy rate (0% and 8%, p?=?0.491) but the FSH cycles were 4.8 times more expensive. Letrozole and FSH were both effective in treating women with CC-resistant PCOS but letrozole was more cost effective.Study registration number: NCT02304107.     

人绝经期促性腺激素联合氯米芬或来曲唑用于多囊卵巢综合征患者促排卵疗效比较

的探讨人绝经期促性腺激素（HMG）＋氯米芬（CC）、HMG和来曲唑（LE）＋HMO对多囊卵巢综合征（PCOS）患者宫腔内供精人工授精的治疗效果。方法将2007年12月-2008年5月期间在我中心就诊的114例PCOS妇女的114个宫腔内人工授精（AID）周期分为3组：CC＋HMG周期组38个周期，HMG周期组38个周期，LE＋HMG周期组38个周期。分析比较3组的年龄、血清T水平、绒毛膜促性腺激素肌肉注射日（HCG日）平均卵泡直径（MFD）≥14mm的卵泡（成熟卵泡）个数、平均卵泡E2水平、子宫内膜厚度、HCG日单优势卵泡发育成熟百分率、HMG用量和周期妊娠率。结果CC＋HMG组、HMG组和LE＋HMG组患者年龄和血清T水平比较，差异无显著性（P〉0．05），CC＋HMG组HCG日成熟卵泡个数为（2．9±1．6）个，明显多于其他两组[HMG组为（1．6±1．0）个，LE＋HMG组为（1．9±1．2）个]，差异有显著性（P〈0．05），而内膜厚度较其他两组薄，差异有显著性（P〈0．05），HMG组与LE＋HMG组HCG日成熟卵泡个数和子宫内膜厚度比较，差异无显著性（P〉0．05）。3组HCG日单优势卵泡发育成熟百分率分别21．05％、78．95％和52．63％，差异有显著性（P〈0．05）。CC＋HMG组、HMG组和LE＋HMG组HMG用量分别为（4．89±1．59）支和（9．88±4．59）支、（9．68±4．67）支（75IU／支），CC＋HMG组与后两组比较，差异有显著性（P=0．00）。HMG组、LE＋HMG组HMG用量比较，差异无显著性（P〉0．05）。3组的周期妊娠率分别为36．84％、39．48％和31．57％，差异无显著性（P〉0．05）。结论HMG促排卵周期更易得到单优势卵泡发育成熟；CC＋HMG促排卵HMG用药量最少；CC＋HMG、HMG和LE＋HMG均可获得满意的周期妊娠率。     

Effects of letrozole on superovulation with gonadotropins in women undergoing intrauterine insemination

OBJECTIVE: To investigate the effects of letrozole in patients undergoing superovulation with gonadotropins and IUI. DESIGN: Retrospective analysis. SETTING: Academic teaching hospital. PATIENT(S): Women younger than 40 years of age with patent fallopian tubes and infertility of more than 1 year in duration who were undergoing IUI and gonadotropin therapy. INTERVENTION(S): Gonadotropins alone administered from day 3 or a combination of letrozole, 5 mg/d on day 3 to 7, and gonadotropins starting on day 5 of the menstrual cycle. Ultrasonography was performed before initiation of treatment, on day 9 of menstrual cycle, and as required thereafter until the dominant follicle reached 18 mm in diameter. Ovulation was triggered with 10,000 IU of hCG, and IUI was performed 24 and 48 hours later. MAIN OUTCOME MEASURE(S): Gonadotropin requirements, endometrial thickness, number of follicles, and pregnancy rate. RESULT(S): All 205 IUI treatment cycles conducted from March 2001 to March 2002 were included. Gonadotropins alone were used in 145 cycles and combination therapy was used in 60 cycles. Patients cotreated with letrozole required fewer gonadotropin administrations (median difference, 300 IU [95% confidence interval (CI), 225-375 IU]), developed more follicles larger than 14 mm (median difference, 1 follicle [95% CI, 1-2 follicles), and had a thinner endometrium (median difference, 1 mm [95% CI, 0.4-1.6 mm]). The pregnancy rate did not differ between patients using gonadotropin alone and those using gonadotropin plus letrozole (20.9% vs. 21.6%). CONCLUSION(S): The addition of letrozole to gonadotropins decreases gonadotropin requirements, increases the number of pre-ovulatory follicles and decreases endometrial thickness, without a negative effect on pregnancy rates.     

Combined metformin and clomiphene citrate versus highly purified FSH for ovulation induction in clomiphene-resistant PCOS women: a randomised controlled trial

Aim.?To compare the effect of combined metformin–clomiphene citrate (CC) with highly purified urinary FSH (HP-uFSH) for ovulation induction in CC-resistant women with polycystic ovary syndrome (PCOS).

Methods.?One-hundred fifty-three anovulatory women with CC-resistant PCOS were selected in this randomised controlled trial. Patients received combined metformin–CC (n?=?75, 205 cycles) or HP-uFSH (n?=?78, 186 cycles) for three cycles. Outcome measures were; Ovulation rate, number of growing and mature follicles, serum E2, serum P, endometrial thickness, pregnancy and miscarriage rates.

Results.?The ovulation rate per cycle was significantly higher in the HP-uFSH group (83.8% vs. 62%, p?=?0.01). The number of follicles ≥12?mm ≥14?mm and ≥18?mm on the hCG day was significantly greater in the HP-uFSH group (p?=?0.01, p?=?0.02 and p?=?0.03, respectively). Pregnancy occurred in 23/205 cycles (11.2%) in combined metformin–CC group and 40/186 cycles (21.5%) in the HP-uFSH group; the difference was statistically significant (p?=?0.02). Two patients in the HP-uFSH group suffered mild OHSS.

Conclusions.?Combined metformin–CC resulted in modest ovulation and pregnancy rates without side effects. It is logical to offer this first for CC-resistant PCOS women before resorting to more expensive alternatives especially in developing communities where economic aspects of therapy are important.     

A randomized comparison of ovulation induction and hormone profile between the aromatase inhibitor anastrozole and clomiphene citrate in women with infertility

Background. In the present study we evaluated and compared the effects of ovulation and hormonal dynamics induced by anastrozole and clomiphene citrate in women with infertility.

Materials and methods. Thirty-three infertile patients, aged 25–41 years, were enrolled. Patients received either anastrozole 1 mg daily (AI group) or clomiphene citrate 100 mg daily (CC group) from cycle day 3 to day 7. Number of mature follicles (≥18 mm), endometrial thickness, pregnancy rate and serial hormone profiles (follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E₂), testosterone and progesterone) were measured on cycle day 3, day 8, day 10, the day of intrauterine insemination (IUI), day 7 after IUI and day 14 after IUI.

Results. Baseline parameters were similar in the two groups, including age, body mass index, infertility duration and day-3 serum hormones except FSH. The mean FSH value on day 3 was significantly different (4.3 mIU/ml in the AI group vs. 6.3 mIU/ml in the CC group; p < 0.05). The women receiving anastrozole had fewer ovulatory follicles (1.2 in the AI group vs. 1.8 in the CC group; p < 0.05) and a thicker endometrium (10.6 mm in the AI group vs. 7.8 mm in the CC group; p < 0.05). The levels of progesterone and testosterone were similar during ovulation stimulation cycles in both groups. On the other hand, the AI group had a significantly higher LH level but a significantly lower E₂ level in the stimulation cycle.

Conclusion. Anastrozole has a high pregnancy rate, although it induces fewer ovulatory follicles compared with clomiphene citrate. The two drugs gave different responses of FSH, LH and E₂ during stimulation cycles.