Effects of Letrozole-HMG and Clomiphene-HMG on Incidence of Luteinized Unruptured Follicle Syndrome in Infertile Women Undergoing Induction Ovulation and Intrauterine Insemination: A Randomised Trial

Extending letrozole treatment duration is effective in inducing ovulation in women with polycystic ovary syndrome and letrozole resistance

OBJECTIVE

To evaluate whether extending letrozole (LE) treatment duration could induce ovulation in women with polycystic ovary syndrome (PCOS) who previously failed to ovulate after a 5-day regimen of 5 mg LE daily for at least 1 ovulation induction cycle, defined as "LE resistance".

DESIGN

Retrospective cohort study.

SETTING

Tertiary care academic medical center.

PATIENT(S)

A total of 69 women with PCOS and LE resistance were included.

INTERVENTION(S)

The duration of LE treatment was increased in a stepwise manner (named as "2-step extended LE regimen"): a 7-day regimen of 5 mg LE daily was prescribed in the first ovulation induction cycle, and if ovulation did not occur, a 10-day regimen was prescribed in the subsequent cycle.

MAIN OUTCOME MEASURE(S)

Ovulation rate was the primary outcome. Clinical pregnancy rate, live birth rate, spontaneous ovulation rate, and ovarian hyperstimulation syndrome rate were the secondary outcomes.

RESULT(S)

Of the 69 patients, 48 ovulated after the 7-day and 16 after the 10-day regimen. Overall, the cumulative ovulation rate reached 92.75% (64/69) after the 2-step extended LE regimen, with a cumulative clinical pregnancy rate of 31.88% (22/69) and a cumulative live birth rate of 24.63% (17/69). All patients ovulated spontaneously without exogenous trigger agents and none experienced ovarian hyperstimulation syndrome.

CONCLUSION(S)

Extending LE treatment duration is a feasible method for inducing ovulation in women with PCOS and LE resistance.

Luteinised unruptured follicle syndrome: pathophysiological background and new target therapy in assisted reproductive treatments

Luteinised unruptured follicle syndrome (LUFS) is a cause of infertility consisting in the unruptured of the dominant follicle after the LH-surge. In fact, during assisted reproductive treatments (ART) clomiphene citrate and letrozole are frequently administered in order to achieve ovulation. However, considering the pathophysiology of LUFS, new possible therapy can be proposed. On this scenario, we performed a review of the literature searching for LUFS recurrency and its impact in infertility and ART. An inflammation theory has been proposed that can be fuel for further therapeutic possibilities. In particular, considering the increase in granulocytes accumulation, the granulocyte colony-stimulating factor (G-CSF) administration has been proposed as target therapy in IUI cycles hampered by LUFS. Although data are encouraging, randomised controlled trials are needed in order to confirm the efficacy of G-CSF administration for LUFS patients.

Aromatase inhibitors (letrozole) for ovulation induction in infertile women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common cause of infrequent periods (oligomenorrhoea) and absence of periods (amenorrhoea). It affects about 5% to 20% of women worldwide and often leads to anovulatory infertility. Aromatase inhibitors (AIs) are a class of drugs that were introduced for ovulation induction in 2001. Since about 2001 clinical trials have reached differing conclusions as to whether the AI, letrozole, is at least as effective as the first-line treatment clomiphene citrate (CC), a selective oestrogen receptor modulator (SERM).

OBJECTIVES

To evaluate the effectiveness and safety of AIs (letrozole) (with or without adjuncts) compared to SERMs (with or without adjuncts) for infertile women with anovulatory PCOS for ovulation induction followed by timed intercourse or intrauterine insemination.

SEARCH METHODS

We searched the following sources, from their inception to 4 November 2021, to identify relevant randomised controlled trials (RCTs): the Cochrane Gynaecology and Fertility Group Specialised Register, CENTRAL, MEDLINE, Embase and PsycINFO. We also checked reference lists of relevant trials, searched the trial registers and contacted experts in the field for any additional trials. We did not restrict the searches by language or publication status.

SELECTION CRITERIA

We included all RCTs of AIs used alone or with other medical therapies for ovulation induction in women of reproductive age with anovulatory PCOS.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, extracted the data and assessed risks of bias using RoB 1. We pooled trials where appropriate using a fixed-effect model to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for most outcomes, and risk differences (RDs) for ovarian hyperstimulation syndrome (OHSS). The primary outcomes were live birth rate and OHSS rate. Secondary outcomes were clinical pregnancy, miscarriage and multiple pregnancy rates. We assessed the certainty of the evidence for each comparison using GRADE methods.

MAIN RESULTS

This is a substantive update of a previous review; of six previously included trials, we excluded four from this update and moved two to 'awaiting classification' due to concerns about validity of trial data. We included five additional trials for this update that now includes a total of 41 RCTs (6522 women). The AI, letrozole, was used in all trials. Letrozole compared to SERMs with or without adjuncts followed by timed intercourse Live birth rates were higher with letrozole (with or without adjuncts) compared to SERMs followed by timed intercourse (OR 1.72, 95% CI 1.40 to 2.11; I2 = 0%; number needed to treat for an additional beneficial outcome (NNTB) = 10; 11 trials, 2060 participants; high-certainty evidence). This suggests that in women with a 20% chance of live birth using SERMs, the live birth rate in women using letrozole with or without adjuncts would be 27% to 35%. There is high-certainty evidence that OHSS rates are similar with letrozole or SERMs (0.5% in both arms: risk difference (RD) -0.00, 95% CI -0.01 to 0.01; I2 = 0%; 10 trials, 1848 participants; high-certainty evidence). There is evidence for a higher pregnancy rate in favour of letrozole (OR 1.69, 95% CI 1.45 to 1.98; I2 = 0%; NNTB = 10; 23 trials, 3321 participants; high-certainty evidence). This suggests that in women with a 24% chance of clinical pregnancy using SERMs, the clinical pregnancy rate in women using letrozole with or without adjuncts would be 32% to 39%. There is little or no difference between treatment groups in the rate of miscarriage per pregnancy (25% with SERMs versus 24% with letrozole: OR 0.94, 95% CI 0.66 to 1.32; I2 = 0%; 15 trials, 736 participants; high-certainty evidence) and multiple pregnancy rate (2.2% with SERMs versus 1.6% with letrozole: OR 0.74, 95% CI 0.42 to 1.32; I2 = 0%; 14 trials, 2247 participants; high-certainty evidence). However, a funnel plot showed mild asymmetry, indicating that some trials in favour of SERMs might be missing.  Letrozole compared to laparoscopic ovarian drilling (LOD) One trial reported very low-certainty evidence that live birth rates may be higher with letrozole compared to LOD (OR 2.07, 95% CI 0.99 to 4.32; 1 trial, 141 participants; very low-certainty evidence). This suggests that in women with a 22% chance of live birth using LOD with or without adjuncts, the live birth rate in women using letrozole with or without adjuncts would be 24% to 47%. No trial reported OHSS rates. Due to the low-certainty evidence we are uncertain if letrozole improves pregnancy rates compared to LOD (OR 1.47, 95% CI 0.95 to 2.28; I² = 0%; 3 trials, 367 participants; low-certainty evidence). This suggests that in women with a 29% chance of clinical pregnancy using LOD with or without adjuncts, the clinical pregnancy rate in women using letrozole with or without adjuncts would be 28% to 45%. There seems to be no evidence of a difference in miscarriage rates per pregnancy comparing letrozole to LOD (OR 0.65, 95% CI 0.22 to 1.92; I² = 0%; 3 trials, 122 participants; low-certainty evidence). This also applies to multiple pregnancies (OR 3.00, 95% CI 0.12 to 74.90; 1 trial, 141 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

Letrozole appears to improve live birth rates and pregnancy rates in infertile women with anovulatory PCOS, compared to SERMs, when used for ovulation induction, followed by intercourse. There is high-certainty evidence that OHSS rates are similar with letrozole or SERMs. There was high-certainty evidence of no difference in miscarriage rate and multiple pregnancy rate. We are uncertain if letrozole increases live birth rates compared to LOD. In this update, we added good quality trials and removed trials with concerns over data validity, thereby upgrading the certainty of the evidence base.

Downregulation of LHCGR Attenuates COX-2 Expression and Induces Luteinized Unruptured Follicle Syndrome in Endometriosis

An association between endometriosis and luteinized unruptured follicle syndrome (LUFs) has long been identified. Although inactivating mutation of luteinizing hormone/choriogonadotropin receptor (LHGCR) results in LUFs, whether LHCGR contributes to promoting LUFs in endometriosis remains elusive. To investigate the effect of LHCGR signaling in the development of endometriosis-associated LUFs and dissect the underlying mechanism in vivo mouse endometriosis model was established to measure the effect on ovarian folliculogenesis. In vitro cultures of primary human GCs collected from patients undergoing in vitro fertilization were performed and treated with human chorionic gonadotropin (hCG), dibutyryl cyclic-AMP (db-cAMP), LHCGR or CCAAT/enhancer binding protein-α (C/EBPα) small interfering RNA to identify the potential mechanisms. KGN cell line was used to investigate the mechanistic features of transcriptional regulation. Results showed an increased incidence of LUFs was observed in mice with endometriosis. The expression of LHCGR was decreased in the GCs of endometriosis mice. In in vitro cell models, LHCGR signaling increased the expression of C/EBPα and cyclooxygenase-2(COX-2), while inhibiting C/EBPα mitigated the induced COX-2 expression. Mechanically, C/EBPα bounded to the promoter region of COX-2 and increased the transcriptional activity under the stimulation of hCG or db-cAMP. Taken together, this study demonstrated that the LHCGR signaling was reduced in GCs of endometriosis and resulted in a decrease in gonadotropin-induced COX-2 expression. Our study might provide new insights into the dysfunction of GCs in endometriosis.

A Prospective Randomised Comparative Clinical Trial Study of Luteal PhaseLetrozole versus Ganirelix Acetate Administration to Prevent Severity of Early Onset OHSS in ARTs

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is the most notable complication in ovulation induction for assisted reproductive techniques (ARTs) like in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Hence, we decided to evaluate the effect of the aromatase inhibitor, letrozole, versus gonadotrophin-releasing hormone (GnRH)-antagonist (ganirelix acetate) on prevention of severity of OHSS and reduction in serum estradiol (E2) levels when administered during the luteal phase after oocyte retrieval in IVF/ICSI cycles.

MATERIALS AND METHODS

In this prospective single-centred, randomized, parallel-arm study, 122 patients were randomized to receive oral letrozole (n=61, 2.5 mg twice daily) or ganirelix acetate (n=61, 0.25 mg subcutaneously daily) from the day of egg retrieval for the next 7 days. Incidence and severity of early OHSS were the primary endpoints assessed by the signs, symptoms, and laboratory findings of OHSS (e.g., serum E2 levels). The secondary endpoints were patient satisfaction and the additional cost of therapy to prevent the severity of OHSS.

RESULTS

Letrozole group had lower incidence of OHSS (13.1%) compared to 19.6% in ganirelix acetate group (P=0.32). Serum E2 levels on post-pick up days 5 and 7 were significantly lower in the letrozole group when compared to the ganirelix acetate group (P=0.001). The majority of the patients in both groups had no major complications. No significant difference was found between the study groups with respect to the incidence of OHSS (P=0.33). The additional cost per IVF cycle for prevention of severity of early-onset OHSS in the letrozole group was 5.32 USD compared to 267.26 USD in the ganirelix acetate group, which was almost fifty times costlier.

CONCLUSION

Letrozole and ganirelix acetate have the same efficiency for the overall prevention of OHSS, whereas letrozole was more effective in preventing moderate OHSS. Letrozole had better patient satisfaction and is cheaper compared to GnRH antagonists (Registration number: CTRI/2020/10/028674).

Effects of acupuncture on Luteinized Unruptured Follicle Syndrome: A meta-analysis of randomized controlled trials

PURPOSE

This meta-analysis aimed to evaluate the comprehensive efficiency and safety of acupuncture on Luteinized Unruptured Follicle Syndrome based on Randomized Controlled Trials (RCTs).

METHODS

Six electronic databases (i.e. Wanfang, VIP, China National Knowledge Infrastructure, Pubmed, Cochrane, and Embase) were searched from inception to July 2019. Randomized controlled trials were eligible to evaluate the effects of acupuncture alone or acupuncture as an adjunct. The primary outcomes were the ovulation rate and pregnancy rate. Two reviewers proceeded study selection and quality assessment of included trials and performed heterogeneity of included studies before meta-analysis.Trial Sequential Analysis was used to assess the risk of random error and estimate required information size. The Grading of Recommendations Assessment, Development and Evaluation was applied for assessing level of evidence.

RESULTS

10 studies involving 715 participants were included Meta-analysis showed acupuncture alone and acupuncture as an adjunct both could significantly improve ovulation, which were confirmed by Trial Sequential Analysis. The evidence of acupuncture improving pregnancy rate was insufficient. Improved serum luteinizing hormone and estradiol levels, and decreased pulsatility index and resistance index of ovary artery were shown in both two subgroups. Level of evidence of most outcomes was "low" or "very low", so the results should be cautiously interpreted.

CONCLUSIONS

Acupuncture alone or be combined with drugs are effective on Luteinized Unruptured Follicle Syndrome especially for improving ovulation . While concurrent evidence is insufficient, and further studies of high quality are needed to strengthen the conclusion.

Aromatase inhibitors (letrozole) for subfertile women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (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. Aromatase inhibitors (AIs) are a class of drugs that were introduced for ovulation induction in 2001. Since about 2001 clinical trials have reached differing conclusions as to whether the AI letrozole is at least as effective as the first-line treatment clomiphene citrate (CC).

OBJECTIVES

To evaluate the effectiveness and safety of aromatase inhibitors for subfertile women with anovulatory PCOS for ovulation induction followed by timed intercourse or intrauterine insemination (IUI).

SEARCH METHODS

We searched the following sources from inception to November 2017 to identify relevant randomised controlled trials (RCTs): the Cochrane Gynaecology and Fertility Group Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, PsycINFO, Pubmed, LILACS, Web of Knowledge, the World Health Organization (WHO) clinical trials register and Clinicaltrials.gov. We also searched the references of relevant articles. We did not restrict the searches by language or publication status.

SELECTION CRITERIA

We included all RCTs of AIs used alone or with other medical therapies for ovulation induction in women of reproductive age with anovulatory PCOS.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, extracted the data and assessed risks of bias. We pooled studies where appropriate using a fixed-effect model to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for most outcomes, and risk differences (RDs) for ovarian hyperstimulation syndrome (OHSS). The primary outcomes were live birth and OHSS. Secondary outcomes were clinical pregnancy, miscarriage and multiple pregnancy. We assessed the quality of the evidence for each comparison using GRADE methods.

MAIN RESULTS

This is a substantive update of a previous review. We identified 16 additional studies for the 2018 update. We include 42 RCTs (7935 women). The aromatase inhibitor letrozole was used in all studies.Letrozole compared to clomiphene citrate (CC) with or without adjuncts followed by timed intercourseLive birth rates were higher with letrozole (with or without adjuncts) compared to clomiphene citrate (with our without adjuncts) followed by timed intercourse (OR 1.68, 95% CI 1.42 to 1.99; 2954 participants; 13 studies; I² = 0%; number needed to treat for an additional beneficial outcome (NNTB) = 10; moderate-quality evidence). There is high-quality evidence that OHSS rates are similar with letrozole or clomiphene citrate (0.5% in both arms: risk difference (RD) -0.00, 95% CI -0.01 to 0.00; 2536 participants; 12 studies; I² = 0%; high-quality evidence). There is evidence for a higher pregnancy rate in favour of letrozole (OR 1.56, 95% CI 1.37 to 1.78; 4629 participants; 25 studies; I² = 1%; NNTB = 10; moderate-quality evidence). There is little or no difference between treatment groups in the rate of miscarriage by pregnancy (20% with CC versus 19% with letrozole; OR 0.94, 95% CI 0.70 to 1.26; 1210 participants; 18 studies; I² = 0%; high-quality evidence) and multiple pregnancy rate (1.7% with CC versus 1.3% with letrozole; OR 0.69, 95% CI 0.41 to 1.16; 3579 participants; 17 studies; I² = 0%; high-quality evidence). However, a funnel plot showed mild asymmetry, indicating that some studies in favour of clomiphene might be missing.Letrozole compared to laparoscopic ovarian drillingThere is low-quality evidence that live birth rates are similar with letrozole or laparoscopic ovarian drilling (OR 1.38, 95% CI 0.95 to 2.02; 548 participants; 3 studies; I² = 23%; low-quality evidence). There is insufficient evidence for a difference in OHSS rates (RD 0.00, 95% CI -0.01 to 0.01; 260 participants; 1 study; low-quality evidence). There is low-quality evidence that pregnancy rates are similar (OR 1.28, 95% CI 0.94 to 1.74; 774 participants; 5 studies; I² = 0%; moderate-quality evidence). There is insufficient evidence for a difference in miscarriage rate by pregnancy (OR 0.66, 95% CI 0.30 to 1.43; 240 participants; 5 studies; I² = 0%; moderate-quality evidence), or multiple pregnancies (OR 3.00, 95% CI 0.12 to 74.90; 548 participants; 3 studies; I² = 0%; low-quality evidence).Additional comparisons were made for Letrozole versus placebo, Selective oestrogen receptor modulators (SERMS) followed by intrauterine insemination (IUI), follicle stimulating hormone (FSH), Anastrozole, as well as dosage and administration protocols. There is insufficient evidence for a difference in either group of treatment due to a limited number of studies. Hence more research is necessary.

AUTHORS' CONCLUSIONS

Letrozole appears to improve live birth and pregnancy rates in subfertile women with anovulatory polycystic ovary syndrome, compared to clomiphene citrate. There is high-quality evidence that OHSS rates are similar with letrozole or clomiphene citrate. There is high-quality evidence of no difference in miscarriage rates or multiple pregnancy rates. There is low-quality evidence of no difference in live birth and pregnancy rates between letrozole and laparoscopic ovarian drilling, although there were few relevant studies. For the 2018 update, we added good-quality trials, upgrading the quality of the evidence.