Is combined letrozole and clomiphene superior to either as monotherapy: a systemic review and meta-analysis based on clinical trials.

OBJECTIVE: This research was conducted to assess the therapeutic advantage of combined letrozole and clomiphene citrate versus monotherapy for polycystic ovarian syndrome (PCOS) patients. STUDY DESIGN: Five databases were searched using the search string: (letrozole and clomiphene) AND (clomiphene OR clomiphene citrate OR CC) AND (letrozole OR LE) AND (ovulation induc* OR fertility induc* OR fertility preserv*) AND (polycystic ovarian syndrome OR PCOS). All statistical analyses were conducted in Review Manager 5.4.1. Random effect-effect model was used to pool risk ratio (RR), mean difference (MD), and odds ratio (OR) and their corresponding 95% confidence interval (CI). Moreover, qualitative analysis was conducted to qualitatively analyze ovulation, secondary outcomes, and cycle characteristics. RESULTS: One clinical trial and three randomized clinical trials (RCTs) were used in the study. Two studies were used in a quantitative analysis showing that combination was superior for ovulation induction (RR = 1.86 [1.37, 2.53]; p < 0.0001; I2 = 0%), but the number of follicles ≥15 mm was significantly associated with the combination (MD = 0.40[0.14, 0.66]; p = 0.002; I2 = 0%). On subgroup analysis, only hot flushes were significantly associated with the combination (RR = 2.67[1.12, 6.36]; p = 0.03; I2 = 0%). The meta-analysis of two studies reported a significantly higher ovulation rate and number of dominant follicles in the combination therapy group compared with the LE alone arm but no significant difference in pregnancy rate, endometrial thickness, and adverse events. CONCLUSION: Our study demonstrates a significant effect of the combination on ovulation induction. The combination yielded a better chance of conception and viable pregnancy. Further studies are needed to determine the live birth rate. HighlightsCombined Letrozole and Clomiphene is superior to either of these drugs alone for ovulation induction in PCOS.Our results conclude that the combination results in better ovulation, cycle characteristics, and secondary changes.Only the incidence of hot flushes as an adverse effect is increasingly reported in combination.

Competence of Combined Low Dose of Human Chorionic Gonadotropin (HCG) and Clomiphene Citrate (CC) Versus Continued CC during Ovulation Induction in Women with CC-Resistant Polycystic Ovarian Syndrome: A Randomized Controlled Trial.

Background and Objectives: Polycystic ovarian syndrome (PCOS) is a widespread endocrine disorder affecting 5-18% of females in their childbearing age. The aim of this study is to assess the efficacy of combining a low dosage of human chorionic gonadotropin (HCG) along with clomiphene citrate (CC) for stimulating ovulation in infertile women diagnosed with CC-resistant PCOS. Materials and Methods: A randomized controlled trial was carried out on 300 infertile CC-resistant PCOS women. All participants were assigned to two groups: the CC-HCG group and the CC-Placebo group. Subjects in the CC-HCG group were given CC (150 mg/day for 5 days starting on the 2nd day of the cycle) and HCG (200 IU/day SC starting on the 7th day of the cycle). Subjects in the CC-Placebo group were given CC and a placebo. The number of ovarian follicles > 18 mm, cycle cancellation rate, endometrial thickness, ovulation rate, clinical pregnancy rate, and occurrence of early ovarian hyper-stimulation syndrome were all outcome variables in the primary research. Results: Data from 138 individuals in the CC-HCG group and 131 participants in the CC-Placebo group were subjected to final analysis. In comparison to the CC-Placebo group, the cycle cancellation rate in the CC-HCG group was considerably lower. The CC-HCG group exhibited a substantial increase in ovarian follicles reaching > 18 mm, endometrial thickness, and ovulation rate. The clinical pregnancy rate was higher in the CC-HCG group (7.2% vs. 2.3%; CC-HCG vs. CC-Placebo). Upon adjusting for BMI and age, the findings of our study revealed that individuals in the CC-HCG group who had serum prolactin levels below 20 (ng/mL), secondary infertility, infertility duration less than 4 years, baseline LH/FSH ratios below 1.5, and serum AMH levels more than 4 (ng/mL) had a higher likelihood of achieving pregnancy. In the CC-Placebo group, there was a greater prediction of clinical pregnancy for those with serum AMH (<4), primary infertility, serum prolactin ≤ 20 (ng/mL), baseline LH/FSH < 1.5, and infertility duration < 4 years. Conclusions: The use of a small dose of HCG along with CC appeared to be an effective treatment in reducing cycle cancelation, improving the clinical pregnancy rate and ovulation rate in CC-resistant PCOS patients. The trial was registered with Clinical Trials.gov, identifier NCT02436226.

The impact of clomiphene citrate on the endometrium in comparison to gonadotropins in intrauterine insemination cycles: is it thinner and does it matter?

Objective: To determine whether endometrial thickness (EMT) differs between i) clomiphene citrate (CC) and gonadotropin (Gn) utilizing patients as their own controls, and ii) patients who conceived with CC and those who did not. Furthermore, to investigate the association between late-follicular EMT and pregnancy outcomes, in CC and Gn cycles. Methods: Retrospective study. Three sets of analyses were conducted separately for the purpose of this study. In analysis 1, we included all cycles from women who initially underwent CC/IUI (CC1, n=1252), followed by Gn/IUI (Gn1, n=1307), to compare EMT differences between CC/IUI and Gn/IUI, utilizing women as their own controls. In analysis 2, we included all CC/IUI cycles (CC2, n=686) from women who eventually conceived with CC during the same study period, to evaluate EMT differences between patients who conceived with CC (CC2) and those who did not (CC1). In analysis 3, pregnancy outcomes among different EMT quartiles were evaluated in CC/IUI and Gn/IUI cycles, separately, to investigate the potential association between EMT and pregnancy outcomes. Results: In analysis 1, when CC1 was compared to Gn1 cycles, EMT was noted to be significantly thinner [Median (IQR): 6.8 (5.5-8.0) vs. 8.3 (7.0-10.0) mm, p<0.001]. Within-patient, CC1 compared to Gn1 EMT was on average 1.7mm thinner. Generalized linear mixed models, adjusted for confounders, revealed similar results (coefficient: 1.69, 95% CI: 1.52-1.85, CC1 as ref.). In analysis 2, CC1 was compared to CC2 EMT, the former being thinner both before [Median (IQR): 6.8 (5.5-8.0) vs. 7.2 (6.0-8.9) mm, p<0.001] and after adjustment (coefficient: 0.59, 95%CI: 0.34-0.85, CC1 as ref.). In analysis 3, clinical pregnancy rates (CPRs) and ongoing pregnancy rates (OPRs) improved as EMT quartiles increased (Q1 to Q4) among CC cycles (p<0.001, p<0.001, respectively), while no such trend was observed among Gn cycles (p=0.94, p=0.68, respectively). Generalized estimating equations models, adjusted for confounders, suggested that EMT was positively associated with CPR and OPR in CC cycles, but not in Gn cycles. Conclusions: Within-patient, CC generally resulted in thinner EMT compared to Gn. Thinner endometrium was associated with decreased OPR in CC cycles, while no such association was detected in Gn cycles.

The cumulative live birth rate and cost-effectiveness of the clomiphene and gonadotropin cotreatment protocol versus the mid-luteal GnRH agonist protocol in women over 35 years old.

The decrease in assisted reproductive technology success among older women, attributed to decreased oocyte quantity and quality, poses a significant challenge. Currently, no consensus on the optimal ovarian stimulation protocol for older women undergoing IVF exists. This retrospectively registered cohort study aimed to compare the cumulative live birth rate (CLBR), time to live birth (TTLB), and cost-effectiveness among women older than 35 years who were receiving either the gonadotropin-releasing hormone agonist (GnRHa) or clomiphene citrate and gonadotropin cotreatment with ovarian stimulation (CC cotreatment) protocol. To compare treatment outcomes, we performed propensity score matching (PSM) on 2871 IVF cycles in women older than 35 years who received either the GnRHa or CC cotreatment protocol, resulting in 375 cycles in each group. Additionally, a decision tree model was utilized to assess the cost-effectiveness of the two protocols. Following PSM, both groups had similar baseline characteristics. The CC cotreatment protocol resulted in a greater rate of cycle cancellation (13.07% vs. 8.00%, p = 0.032), but the groups maintained comparable fertilization rates and embryo quality. Although the TTLB was longer in the CC cotreatment group, the CLBR per initial cycle (41.07% vs. 45.33%, p = 0.269) and delivery outcomes were similar between the two groups at the 24 months follow-up. Additionally, the average cost per live birth in the CC cotreatment group was 21.27% lower than in the GnRHa group (¥32,301.42 vs. ¥39,174.22). In conclusion, for women older than 35 years undergoing IVF, the CC cotreatment protocol offered a comparable CLBR to the GnRHa protocol but with reduced costs, indicating its potential as a viable and cost-effective ovarian stimulation option.Clinical trial registration: https://www.chictr.org.cn/ , identifier [ChiCTR2300076537].

Benefit from luteal phase progestin primed ovarian stimulation with clomiphene citrate supplementation in young women with diminished ovarian reserve: a retrospective study. / å¹´è½»åµå·¢å‚¨å¤‡åŠŸèƒ½å‡é€€æ‚£è€ åµæ³¡æœŸä¸Žé»„ä½“æœŸåº”ç”¨é«˜å­•æ¿€ç´ çŠ¶æ€è¶ ä¿ƒæŽ’åµæ–¹æ¡ˆæ•ˆæžœæ¯”è¾ƒ.

OBJECTIVES: To compare the pregnancy outcomes of luteal phase and follicular phase progestin-primed ovarian stimulation protocol with clomiphene citrate supplementation (LPPOS+CC and FPPOS+CC) in young women with diminished ovarian reserve (DOR). METHODS: A total of 483 women aged ≤35 years with DOR, who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI)/embryo transfer (ET) with controlled ovarian stimulation using LPPOS+CC (n=257) or FPPOS+CC (n=226) protocols during June 2018 and December 2021 at the First Affiliated Hospital of Wenzhou Medical University, were included in this retrospective study. The baseline characteristics, superovulation results, laboratory related indicators between the two groups, and the pregnancy outcomes of women who achieved at least one high-quality cleavage-stage embryo or good-morphology blastocyst were compared between the two groups. RESULTS: No statistically significant differences were identified between the groups with respect to age, duration of infertility, proportion of secondary infertility, previous failed cycles, body mass index, anti-Müllerian hormone, antral follicle count, basal luteinizing hormone level, basal progesterone level, number of oocytes retrieved, oocyte maturation rate, high-quality cleavage-stage embryo cycle rate, the percentage of women with profound pituitary suppression, live birth rate and preterm birth rate (all P>0.05). The LH levels on the day of trigger [4.0 (2.7, 5.3) vs. 5.1 (3.2, 7.2) IU/L], the percentage of women with LH levels of >10 IU/L on the trigger day (3.13% vs. 10.67%), and the two pronucleus (2PN) rate of ICSI oocytes (72.16% vs. 79.56%) were significantly lower in the LPPOS+CC group than those in the FPPOS+CC group (P<0.05 or P<0.01). The duration of stimulation [11 (9, 12) vs. 9 (8, 11) d], the consumption of total gonadotropin [2213 (1650, 2700) vs. 2000 (1575, 2325) IU], the progesterone levels on the day of trigger [1.3 (0.8, 2.9) vs. 0.9 (0.6, 1.2) ng/mL], the clinical pregnancy rate [61.88% vs. 46.84%], and implantation rate [42.20% vs. 31.07%] in the LPPOS+CC group were significantly higher than those in the FPPOS+CC group (all P<0.01). CONCLUSIONS: Compared to FPPOS+CC, the LPPOS+CC protocol appears to have better pregnancy outcomes for young women with DOR undergoing IVF/ICSI-ET.

Post-Conceptional Exposure to Clomiphene Citrate and Congenital Malformations: A Cohort Study.

BACKGROUND: Clomiphene citrate is an ovulation inductor for which inadvertent post-conceptional exposures may occur in early pregnancy. In preclinical studies, post-conceptional exposures showed a teratogenic effect in different species. In humans, to date, little is known about the outcomes of inadvertently post-conceptionally exposed pregnancies. OBJECTIVES: The objectives of our study were to assess the association between post-conceptional exposures to clomiphene citrate and major and minor congenital malformations in the offspring. METHODS: A retrospective cohort study of prospectively ascertained cases was undertaken, based on clinical data from the Centre de Référence sur les Agents Tératogènes (CRAT), Paris, France. Women with post-conceptional exposure to clomiphene citrate (n = 309), and unexposed pregnant women (n = 1236, 1:4 ratio) with prospectively collected data, known pregnancy outcome and delivery date prior to 01/02/2022, were matched by calendar year. An adjudication committee classified major and minor congenital malformations according to the EUROCAT (European Registration of Congenital Anomalies and Twins) classification. RESULTS: Among post-conceptional exposed women, no increased risk of major malformation was found (crude relative risk = 0.64, 95% confidence interval 0.19-2.15) as compared to unexposed women. Three major and ten minor congenital malformations were reported in the exposed group. An increased risk of minor malformations was found (crude relative risk = 4.05, 95% confidence interval 1.70-9.64) although there was no specific clinical pattern. CONCLUSIONS: Post-conceptional exposure to clomiphene citrate was not associated with an increased risk of major congenital malformations. Given potential confounding and information biases, the results about minor malformations should be interpreted with caution as no specific clinical pattern was identified.

Long-term use of clomiphene in male macroprolactinomas with persistent hypogonadism.

BACKGROUND: Men with macroprolactinoma can present persistent hypogonadism despite normoprolactinemia achieved with clinical and/or neurosurgical treatment. Usually, testosterone replacement therapy is indicated. Nevertheless, although off-label, clomiphene citrate (CC), a selective estrogen receptor modulator, has also been used, mainly when fertility is an issue. The aim of this study is to evaluate the effectiveness of CC in recovering the gonadal axis in men with macroprolactinoma, with or without hyperprolactinemia, and evaluate its safety as a long-term therapy. METHODS: This is a retrospective study including 10 men with macroprolactinoma on cabergoline treatment and persistent hypogonadism. All patients received initially 50 mg/d of CC. RESULTS: The median age at diagnosis of prolactinomas was 34 (range, 26-60) years old. All patients were treated with cabergoline at a median maximum dose of 2 (1-7) mg/week, with a median time of treatment of 8.5 (2-15) years. Prolactin was still above the normal range when CC was introduced only in two patients. The mean duration of CC therapy was 3.2 (±2.8) years. Prolactin levels maintained stable (p = 0.252) and testosterone increased (p = 0.027) significantly on CC therapy. Tumor size remained stable. Eight patients (80%) maintained testosterone above 300 ng/dL and were classified as responders. Three responders succeeded in using a lower dose of CC and one of them completed withdrawal CC and maintained eugonadism. There were no side effects or safety concerns reported. CONCLUSION: CC should be seen as a safe treatment option for men with macroprolactinoma and persistent hypogonadism.

Clomiphene Citrate Administered in Periconception Phase Causes Fetal Loss and Developmental Impairment in Mice.

Clomiphene citrate is a common treatment for ovulation induction in subfertile women, but its use is associated with elevated risk of adverse perinatal outcomes and birth defects. To investigate the biological plausibility of a causal relationship, this study investigated the consequences in mice for fetal development and pregnancy outcome of periconception clomiphene citrate administration at doses approximating human exposures. A dose-dependent adverse effect of clomiphene citrate given twice in the 36 hours after mating was seen, with a moderate dose of 0.75 mg/kg sufficient to cause altered reproductive outcomes in 3 independent cohorts. Viable pregnancy was reduced by 30%, late gestation fetal weight was reduced by 16%, and ∼30% of fetuses exhibited delayed development and/or congenital abnormalities not seen in control dams, including defects of the lung, kidney, liver, eye, skin, limbs, and umbilicus. Clomiphene citrate also caused a 30-hour average delay in time of birth, and elevated rate of pup death in the early postnatal phase. In surviving offspring, growth trajectory tracking and body morphometry analysis at 20 weeks of age showed postweaning growth and development similar to controls. A dysregulated inflammatory response in the endometrium was observed and may contribute to the underlying pathophysiological mechanism. These results demonstrate that in utero exposure to clomiphene citrate during early pregnancy can compromise implantation and impact fetal growth and development, causing adverse perinatal outcomes. The findings raise the prospect of similar iatrogenic effects in women where clomiphene citrate may be present in the periconception phase unless its use is well-supervised.

Ceiling effect of clomiphene citrate on the testosterone to estradiol ratio in eugonadal infertile men.

INTRODUCTION: The testosterone to estradiol ratio (T/E2 ratio) reportedly exerts a stronger effect on semen quality and sexual desire than does testosterone alone. Clomiphene citrate is a selective estrogen receptor modulator that has long been used as an empirical treatment option in the management of idiopathic oligozoospermia. Clomiphene may change the hypothalamus-pituitary-gonad axis and result in the alteration of the T/E2 ratio. No reliable data are available regarding the change in the T/E2 ratio after clomiphene use in eugonadism. METHODS: This study included 24 male patients who were diagnosed with idiopathic infertility with eugonadism. They all received clomiphene citrate (25 mg/day) as empirical treatment. Blood tests for serum testosterone, estradiol, prolactin, luteinizing hormone, and follicle stimulating hormone were performed before and after 4 weeks of clomiphene use. Paired t-tests were used to evaluate the significance of the hormone level change. RESULTS: Overall, the patients' T/E2 ratio did not increase significantly after clomiphene use. In the subgroup analysis, the T/E2 ratio of patients with a baseline ratio of <200 increased significantly after clomiphene use. CONCLUSIONS: Clomiphene citrate may significantly increase the T/E2 ratio in eugonadal men under the premise of its ceiling effect (T/E2 ratio < 200), providing practitioners with guidance on the use of clomiphene in this demographic.

Application of Pulsed Rhythmic Drug Administration to Ovulation Induction Therapy in PCOS Patients with Clomiphene-Resistance: a Retrospective Research.

There is currently a dispute over the choice of ovulation induction treatment for infertile women with polycystic ovary syndrome (PCOS). The objective of this study is to compare the therapeutic effect of pulsed rhythmic administration protocol (PRAP) with conventional letrozole + human menopausal gonadotropin (HMG) in patients with clomiphene-resistance polycystic ovary syndrome (PCOS). A retrospective analysis of 821 intrauterine insemination (IUI) cycles between January 2015 and January 2020 was performed. Of these, 483 cycles were treated with a pulsed rhythmic administration protocol (PRAP), and 338 cycles were treated with conventional letrozole + HMG protocol (LHP). The therapeutic effect of the two protocols has been compared. The pregnancy rate was 18.07% in the LHP and 27.07% in the PRAP. The ongoing pregnancy rate in LHP was 14.46% and in PRAP was 22.73%. The research suggests that PRAP is more effective than LHP and could be an adequate ovulation induction strategy for the IUI cycle of patients with clomiphene-resistance PCOS.

Does the additional use of clomiphene citrate or letrozole for in vitro fertilization deserve more attention?

BACKGROUND: Adding clomiphene citrate (CC) and/or letrozole (LE) to in vitro fertilization (IVF) cycles for mild ovarian stimulation is a general approach. Although lots of researches have demonstrated partial benefits of the strategy, all-around effects of oral medications remained deficient. This paper aims to assess whether an addition of oral medication will result in considerable outcomes on T-Gn (total dose of gonadotropin), Gn days, total retrieved ova, high quality embryos, blastocyst number, ovarian hyperstimulation syndrome (OHSS) rate, clinical pregnancy rate and cumulative pregnancy rate, even if it was not conventional mild/minimal stimulations. RESULTS: Participants were categorized to three diverse populations as high responders, normal responders and poor responders according to basal antral follicle count. T-Gn in patients treated with CC/LE distinctly decreased from 2496.96 IU/d to 1827.68 IU/d, from 2860.28 IU/d to 2119.99 IU/d, and from 3182.15 IU/d to 1802.84 IU/d, respectively. For high ovary responders and normal responders, the OHSS incidence rate also declined from 29.2 to 4.3% (P < 0.001) and from 1.1 to 0.0% (P = 0.090). Other, there was no statistical difference with respect to the T-retrieved ova (total retrieved ova), high quality embryos, cultured blastocyst and blastocyst number in high responders. For normal responders and poor ovary responders, T-Gn, Gn days, T-retrieved ova, high quality embryos, cultured blastocyst and blastocysts number in oral medications group all apparently decreased. Clinical pregnancy rate per fresh cycle of poor responders with prior oral medications was significantly decreased (25.7% vs. 50.8%, P = 0.005), and no significant differences in high responders and normal responders were expressed (52.5% vs. 44.2%, P = 0.310; 51.9% vs. 42.4%, P = 0.163) between two groups of participants. The numbers of cumulative pregnancy rates were lower in the conventional group compared to the add group for high (75.90% versus 81.03%, P = 0.279), normal (62.69% versus 71.36%, P = 0.016) and poor (39.74% versus 68.21%, P < 0.001) responders. CONCLUSIONS: The addition of CC/LE to the ovulation induction during IVF has certain efficacy in terms of low cost, low OHSS incidence. CC/LE deserves more recommendations as a responsible strategy in high responders due to advantageous pregnancy outcomes. For normal responders, the strategy needs to be considered with more comprehensive factors.

Anabolic steroid use and ischaemic stroke in a young fitness enthusiast.

We report a case of ischaemic stroke in a 34-year-old male recreational bodybuilder following a 3-month period of anabolic androgenic steroid (AAS) use and 1-month period of 'post-cycle therapy' (tamoxifen and clomiphene citrate), the latter treatments aimed at restoring normal endogenous testosterone production after initial AAS use. We hypothesise a transient drug-related prothrombotic state with paradoxical embolisation via an atrial septal defect which was later found on bubble echocardiogram. We highlight a rare but important cause of stroke in younger patients which is relevant given the increasing use of AAS misuse among casual fitness enthusiasts. We explore the various possible mechanisms by which AAS use can increase ischaemic stroke risk in such patients.

Progestin-Primed Ovarian Stimulation with Clomiphene Citrate Supplementation May Be More Feasible for Young Women with Diminished Ovarian Reserve Compared with Standard Progestin-Primed Ovarian Stimulation: A Retrospective Study.

PURPOSE: The present study was designed to compare the efficiency of the progestin-primed ovarian stimulation (PPOS) protocol with clomiphene citrate (CC) supplementation (PPOS+CC) and the standard PPOS protocol for women of different ages with diminished ovarian reserve (DOR). PATIENTS AND METHODS: This retrospective cohort study included 364 DOR women who underwent controlled ovarian stimulation with PPOS+CC (n = 223) or standard PPOS (n = 141). They were divided into subgroups based on age: ≤35 years and >35 years. Differences in baseline characteristics, ovarian stimulation characteristics, endocrinological characteristics, and clinical outcome between the two groups were assessed. Statistical analyses were stratified by age. RESULTS: In all women with DOR, PPOS+CC was associated with a lower percentage of women with profound pituitary suppression than standard PPOS (0.0% vs 18.6%, P < 0.001 and 1.3% vs 11.0%, P = 0.002). In young women with DOR, more high-quality cleavage-stage embryos were harvested (1.96 vs 1.38, P = 0.018) and a lower dosage of gonadotropin per oocyte retrieved was required (558.37 vs 909.82, P = 0.036) in PPOS+CC. In older women with DOR, PPOS+CC led to an increase in the incidence of luteinizing hormone (LH) surge levels above 10 IU/L on trigger day (12.7% vs 4.9%, P = 0.028) and a decrease in the rate of oocyte maturation (84.7% vs 89.9%, P = 0.034) compared to standard PPOS. CONCLUSION: Clomiphene citrate is an effective adjuvant to alleviate pituitary suppression in PPOS protocols; for young women with DOR, CC supplementation had a positive impact on the number of high-quality embryos. However, older women with DOR would be at risk of developing a premature LH surge and having poor oocyte maturation rate under the PPOS+CC protocol.

Letrozole versus clomiphene citrate for ovulation induction in anovulatory women with polycystic ovarian syndrome: A randomized controlled trial.

OBJECTIVE: To compare the efficacy of letrozole and clomiphene citrate (CC) for ovulation induction in infertile women with polycystic ovarian syndrome (PCOS). METHODS: In this assessor blind, randomized controlled trial, 90 infertile women with PCOS were randomized to receive either letrozole or CC for ovulation induction in incremental doses for a maximum of three cycles. Main outcome measures studied were endometrial thickness, ovulation rate, pregnancy rate, rate of monofollicular development, and time to conception. RESULTS: Mean endometrial thicknesses were 9.86 ± 2.32 mm and 9.39 ± 2.06 mm with letrozole and CC, respectively (P=0.751). Cumulative ovulation rates were 86.7% and 85.2% with letrozole and CC, respectively (P=0.751). Pregnancy was achieved in 42.2% of women in the letrozole group and 20.0% of women in the CC group (P=0.04). Monofollicular development was seen in 68.4% of ovulatory cycles in the letrozole group compared with 44.8% in the CC group (P=0.000). Mean time to achieve pregnancy was significantly shorter (log rank P=0.042) with letrozole (9.65 weeks) than with CC (11.07 weeks). CONCLUSION: Letrozole is a better alternative for ovulation induction in anovulatory women with PCOS as pregnancy rates are higher, time to pregnancy is shorter, and chances of multiple pregnancy are less because of high monofollicular growth.

Endometrial thickness after ovarian stimulation with gonadotropin, clomiphene, or letrozole for unexplained infertility, and association with treatment outcomes.

OBJECTIVE: To study the association of endometrial thickness (EMT) with live birth rates (LBR) in ovarian stimulation with intrauterine insemination (OS-IUI) treatments for unexplained infertility. DESIGN: Prospective cohort analysis of the Reproductive Medicine Network's Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation (AMIGOS) randomized controlled trial. SETTING: Multicenter randomized controlled trial. PATIENTS: A total of 868 couples with unexplained infertility (n=2,459 cycles). INTERVENTIONS: OS-IUI treatment cycles (n = 2,459) as part of the AMIGOS clinical trial. MAIN OUTCOME MEASURES: Live birth rates; unadjusted and adjusted risk ratios (RR) for live birth by EMT category, calculated using generalized estimating equations. RESULTS: The overall mean EMT on day of human chorionic gonadotropin administration in cycles with a live birth was significantly greater than in those without. Compared to the referent EMT group of 9 to 12 mm, the unadjusted RR for live birth for the EMT groups of ≤5 and 6-8 were 0.48 and 0.92, respectively. The test for trend indicated evidence of decreasing LBR with decreasing EMT. After adjustment for ovarian stimulation medication, a linear trend was no longer supported. Stratified analyses revealed no differences in associations by treatment group. CONCLUSIONS: In OS-IUI for unexplained infertility, higher LBR are observed with increasing EMT; however, EMT is not significantly associated with LBR when adjusted for OS treatment type. Appreciable LBR are seen at all EMT, even those of ≤5 mm, suggesting that OS-IUI cycles should not be canceled for thin endometrium. CLINICAL TRIAL REGISTRATION NUMBER: NCT01044862.

Optimal lead follicle size for human chorionic gonadotropin trigger in clomiphene citrate and intrauterine insemination cycles: an analysis of 1,676 treatment cycles.

OBJECTIVE: To identify the optimal lead follicle size for hCG trigger in clomiphene citrate (CC)-intrauterine insemination (IUI) cycles. DESIGN: Retrospective cohort study. SETTING: University-affiliated center. PATIENT(S): Patients <40 years of age with ovulatory dysfunction or unexplained infertility undergoing their first CC-IUI cycle. INTERVENTION(S): Ovulation induction, hCG trigger, and IUI. MAIN OUTCOME MEASURE(S): Clinical pregnancy rate (CPR) was the primary outcome and was plotted against lead follicle size in increments of 1 mm. Odds ratios with 95% confidence intervals for associations between lead follicle size and CPR were calculated from a multivariable logistic regression model. A receiver operating characteristic (ROC) curve was generated for CPR as a function of lead follicle size. RESULT(S): 1,676 cycles were included. The overall CPR was 13.8% (232/1,676). There was no difference in baseline demographics or ovulation induction parameters of patients who did or did not conceive. The odds of clinical pregnancy were 2.3 and 2.2 times higher with lead follicle sizes of 21.1-22.0 mm and >22.0 mm, respectively, compared with the referent category of 19.1-20.0 mm. Lead follicle size was an independent predictor of CPR, even after accounting for confounders. A lead follicle size of 22.1 mm corresponded to a sensitivity and specificity of 80.1% and 90.4% for clinical pregnancy, respectively, with an area under the ROC curve of 0.89. CONCLUSION(S): hCG administration at a lead follicle size of 21.1-22.0 mm is associated with higher odds of clinical pregnancy in patients undergoing their first CC-IUI cycles for ovulatory dysfunction or unexplained infertility.

Anti-Müllerian hormone is correlated with cumulative live birth in minimal ovarian stimulation with clomiphene citrate: a retrospective cohort study.

BACKGROUND: Several studies have investigated the correlation between the serum anti-Müllerian hormone (AMH) level and in vitro fertilization (IVF) outcomes in controlled ovarian stimulation cycles; however, studies regarding the correlation of the serum AMH level with IVF outcomes in minimal ovarian stimulation cycles remain limited. In this study, we aimed to analyze the correlation of the serum AMH level with ovarian responsiveness, embryonic outcomes, and cumulative live birth rates in clomiphene citrate (CC)-based minimal ovarian stimulation cycles. METHODS: Clinical records of 689 women whose entire ovarian stimulation regimen consisted solely of minimal stimulation cycle IVF using CC alone from November 2017 to October 2019 were retrospectively reviewed. The association between IVF outcomes and the serum AMH level before the initiation of the first fertility treatment was analyzed. Furthermore, the correlation of the serum AMH level with cumulative live birth rates after IVF treatment was assessed. The Cochran-Armitage test, Pearson's chi-squared test, Spearman rank correlation test, Student's t-test, one-way analysis of variance, logistic regression analysis, Kaplan-Meier method and Cox proportional hazards model were used to analyze the data. RESULTS: The serum AMH level positively correlated with the number of retrieved oocytes, blastocyst formation rate, blastocyst cryopreservation rate, and live birth rate per oocyte retrieval in CC-based minimal ovarian stimulation cycles without any exogenous gonadotropin administration. Furthermore, the cumulative live birth rate and treatment period required for conceiving were strongly associated with the serum AMH level at the initiation of fertility treatment. CONCLUSIONS: A low serum AMH level correlated with low ovarian responsiveness, impaired pre-implantation embryonic development, and decreased cumulative live birth rate in CC-based minimal ovarian stimulation cycles. Therefore, the cycle success rate would be predicted by measuring the serum AMH level in minimal ovarian stimulation with CC alone.

Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes.

BACKGROUND: A frozen embryo transfer (FET) cycle is when one or more embryos (frozen during a previous treatment cycle) are thawed and transferred to the uterus. Some women undergo fresh embryo transfer (ET) cycles with embryos derived from donated oocytes. In both situations, the endometrium is primed with oestrogen and progestogen in different doses and routes of administration. OBJECTIVES: To evaluate the most effective endometrial preparation for women undergoing transfer with frozen embryos or embryos from donor oocytes with regard to the subsequent live birth rate (LBR). SEARCH METHODS: The Cochrane Gynaecology and Fertility Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, LILACS, trials registers and abstracts of reproductive societies' meetings were searched in June 2020 together with reference checking and contact with study authors and experts in the field to identify additional studies. SELECTION CRITERIA: Randomised controlled trials (RCTs) evaluating endometrial preparation in women undergoing fresh donor cycles and frozen embryo transfers. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. We analysed all available interventions versus placebo, no treatment, or between each other. The primary review outcome was live birth rate. Secondary outcomes were clinical and multiple pregnancy, miscarriage, cycle cancellation, endometrial thickness and adverse effects. MAIN RESULTS: Thirty-one RCTs (5426 women) were included. Evidence was moderate to very low-quality: the main limitations were serious risk of bias due to poor reporting of methods, and serious imprecision. Stimulated versus programmed cycle We are uncertain whether a letrozole-stimulated cycle compared to a programmed cycle, for endometrial preparation, improves LBR (odds ratio (OR) 1.26, 95% confidence interval (CI) 0.49 to 3.26; 100 participants; one study; very low-quality evidence). Stimulating with follicle stimulating hormone (FSH), letrozole or clomiphene citrate may improve clinical pregnancy rate (CPR) (OR 1.63, 95% CI 1.12 to 2.38; 656 participants; five studies; I2 = 11%; low-quality evidence). We are uncertain if they reduce miscarriage rate (MR) (OR 0.79, 95% CI 0.36 to 1.71; 355 participants; three studies; I2 = 0%; very low-quality evidence). Endometrial thickness (ET) may be reduced with clomiphene citrate (mean difference(MD) -1.04, 95% CI -1.59 to -0.49; 92 participants; one study; low-quality evidence). Other outcomes were not reported. Natural versus programmed cycle We are uncertain of the effect from a natural versus programmed cycle for LBR (OR 0.97, 95% CI 0.74 to 1.28; 1285 participants; four studies; I2 = 0%; very low-quality evidence) and CPR (OR 0.79, 95% CI 0.62 to 1.01; 1249 participants; five studies; I2 = 60%; very low-quality evidence), while a natural cycle probably reduces the cycle cancellation rate (CCR) (OR 0.60, 95% CI 0.44 to 0.82; 734 participants; one study; moderate-quality evidence). We are uncertain of the effect on MR and ET. No study reported other outcomes. Transdermal versus oral oestrogens From low-quality evidence we are uncertain of the effect transdermal compared to oral oestrogens has on CPR (OR 0.86, 95% CI 0.59 to 1.25; 504 participants; three studies; I2 = 58%) or MR (OR 0.55, 95% CI 0.27 to 1.09; 414 participants; two studies; I2 = 0%). Other outcomes were not reported. Day of starting administration of progestogen When doing a fresh ET using donated oocytes in a synchronised cycle starting progestogen on the day of oocyte pick-up (OPU) or the day after OPU, in comparison with recipients that start progestogen the day prior to OPU, probably increases the CPR (OR 1.87, 95% CI 1.13 to 3.08; 282 participants; one study, moderate-quality evidence). We are uncertain of the effect on multiple pregnancy rate (MPR) or MR. It probably reduces the CCR (OR 0.28, 95% CI 0.11 to 0.74; 282 participants; one study; moderate-quality evidence). No study reported other outcomes. Gonadotropin-releasing hormone (GnRH) agonist versus control A cycle with GnRH agonist compared to without may improve LBR (OR 2.62, 95% CI 1.19 to 5.78; 234 participants; one study; low-quality evidence). From low-quality evidence we are uncertain of the effect on CPR (OR 1.08, 95% CI 0.82 to 1.43; 1289 participants; eight studies; I2 = 20%), MR (OR 0.85, 95% CI 0.36 to 2.00; 828 participants; four studies; I2 = 0%), CCR (OR 0.49, 95% CI 0.21 to 1.17; 530 participants; two studies; I2 = 0%) and ET (MD -0.08, 95% CI -0.33 to 0.16; 697 participants; four studies; I2 = 4%). No study reported other outcomes. Among different GnRH agonists From very low-quality evidence we are uncertain if cycles among different GnRH agonists improves CPR or MR. No study reported other outcomes. GnRH agonists versus GnRH antagonists GnRH antagonists compared to agonists probably improves CPR (OR 0.62, 95% CI 0.42 to 0.90; 473 participants; one study; moderate-quality evidence). We are uncertain of the effect on MR and MPR. No study reported other outcomes. Aspirin versus control From very low-quality evidence we are uncertain whether a cycle with aspirin versus without improves LBR, CPR, or ET. Steroids versus control From very low-quality evidence we are uncertain whether a cycle with steroids compared to without improves LBR, CPR or MR. No study reported other outcomes. AUTHORS' CONCLUSIONS: There is insufficient evidence on the use of any particular intervention for endometrial preparation in women undergoing fresh donor cycles and frozen embryo transfers. In frozen embryo transfers, low-quality evidence showed that clinical pregnancy rates may be improved in a stimulated cycle compared to a programmed one, and we are uncertain of the effect when comparing a programmed cycle to a natural cycle. Cycle cancellation rates are probably reduced in a natural cycle. Although administering a GnRH agonist, compared to without, may improve live birth rates, clinical pregnancy rates will probably be improved in a GnRH antagonist cycle over an agonist cycle. In fresh synchronised oocyte donor cycles, the clinical pregnancy rate is probably improved and cycle cancellation rates are probably reduced when starting progestogen the day of or day after donor oocyte retrieval. Adequately powered studies are needed to evaluate each treatment more accurately.

Efficacy of clomifene citrate for the treatment of patients with polycystic ovary syndrome: A protocol of systematic review.

BACKGROUND: This study aims to assess the efficacy and safety of clomifene citrate (CC) for the treatment of patients with polycystic ovary syndrome (PCOS). METHODS: In this study, we will comprehensively search MEDLINE, EMBASE, The Cochrane Library, Web of Science, CINAHL, ACMD, PsycINFO, and China National Knowledge Infrastructure for original articles published from their inceptions to the January 1, 2020 without language restrictions. All studies will undergo relevance and a design selecting process. Data from qualified studies will be collected by 2 independent authors. Additionally, we will conduct a risk of bias evaluation using a Cochrane risk of bias tool. We will undertake statistical analysis utilizing RevMan 5.3 software. RESULTS: This study will summarize the up-to-date evidence to investigate the efficacy and safety of CC for the treatment of patients with PCOS. CONCLUSION: The findings of this study will provide helpful evidence of CC for the treatment of patients with PCOS, as well as may help develop treatment guidelines. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42020162818.