Combined metformin and clomiphene citrate versus laparoscopic ovarian diathermy for ovulation induction in clomiphene-resistant women with polycystic ovary syndrome: A randomized controlled trial

Metformin With or Without Clomiphene Citrate Versus Laparoscopic Ovarian Drilling With or Without Clomiphene Citrate to Treat Patients With Clomiphene Citrate-Resistant Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

Introduction: Which is optimal to treat clomiphene citrate-resistant polycystic ovary syndrome (CCR-PCOS) with LOD or metformin remains a problem. There are three inconsistent or even contradictory views.

Objectives: The present meta-analysis aimed to evaluate the effectiveness and safety of Metformin with or without CC and to compare them with LOD with or without CC (Met/Met-CC vs. LOD/LOD-CC) in women with CCR-PCOS who also have anovulation.

Data source: The PubMed, Cochrane, and Embase databases were searched to identify relevant studies reported between 1 Jan 1966 and 31 Aug 2019; the search was updated on 17 May 2022.

Study eligibility criteria: We included randomized controlled trials (RCTs) of CCR-PCOS that had considered Met/Met-CC and LOD/LOD-CC as the exposure variables and fertility as the main outcome variable.

Study appraisal and synthesis methods: We assessed study quality using the Cochrane risk-of-bias tool. The primary effectiveness outcome was live birth/ongoing pregnancy rate and the primary safety outcome was miscarriage rate. A fixed-effect meta-analysis was performed. The robustness of the results was assessed using sensitivity analyses. Meta-regression and subgroup analysis were performed to examine the reasons for heterogeneity. Publication bias was examined using the funnel plot, Egger linear regression, and Begg rank correlation tests. The quality of this meta-analysis was estimated according to the GRADE approach. This meta-analysis has been registered in PROSPERO (CRD42021240156).

Results: Among 71 potentially relevant studies, we included five RCTs in our meta-analysis. We found no difference in effectiveness between Met-CC and LOD in terms of live birth/ongoing pregnancy (RR = 1.02, 95% CI: 0.87–1.21, z = 0.28; p = 0.780), and miscarriage rates (RR = 0.79, 95% CI: 0.46–1.36, z = 0.86; p = 0.390). I2 tests results revealed moderate or no heterogeneity (I2 = 51.4%, p = 0.083; I2= 0.0%; p = 0.952). Sensitivity analysis confirmed the robustness of the results. Funnel plot, Egger linear regression, and Begg rank correlation tests implied no publication bias (p > 0.05). LOD was more expensive than Met (€1050 vs. €50.16). The evidence quality was moderate.

Conclusion: There is no evidence on the difference in the outcomes between the two interventions regarding ovulation, pregnancy, and live birth. As LOD is an invasive procedure and carries inherent risks, the use of Met/Met-CC should be the second-line treatment for women with CCR-PCOS.

Systematic Review Registration: identifier CRD42021240156.

Metformin Alleviates Endometriosis and Potentiates Endometrial Receptivity via Decreasing VEGF and MMP9 and Increasing Leukemia Inhibitor Factor and HOXA10

Background: Endometriosis affects endometrial receptivity, a key factor for successful embryo implantation. Metformin treatment is associated with alleviating the symptoms of endometriosis; however the mechanism of metformin action is unclear. Neoangiogenesis plays an important role in the development and recurrence of endometriosis. In addition, the leukemia inhibitor factor (LIF) and HOXA10 genes are also distinguishing markers of endometriosis (decrease) and endometrial receptivity (increase). This study investigated the therapeutic potentials of metformin and the underlying mechanism using an in vivo rat endometriosis model. Methods: Female Wistar albino mature rats with experimentally induced endometriosis were used in this study. Metformin was administered at doses of 100 mg/kg/d and 200 mg/kg/d. The volume of endometriotic implants was assessed. The protein and mRNA expression of the vascular endothelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), the endometrial receptivity markers, LIF and HOXA10, were measured in the endometrium of rats with endometriosis. Results: Metformin treatment significantly suppressed the growth of endometriotic implants. Further, the expression of VEGF and MMP-9 protein and mRNA in endometriotic implants were significantly reduced. Metformin also significantly upregulated LIF and HOXA10 expression in endometrium from rats with endometriosis. The inhibitory effect of metformin on the growth of endometriotic implants, VEGF and MMP-9, and upregulating effect on LIF and HOXA10, was optimal at a dose of 100 mg/kg/d. Conclusion: Our in vivo data demonstrates that metformin treatment alleviates endometriosis and potentiates endometrial receptivity. The underlying mechanisms are associated with decreased expression of VEGF and MMP-9 genes and upregulation of the LIF and HOXA10 genes. The effect of metformin was optimal at 100 mg/kg/d. These findings provide a potential alternative for women with endometriosis with the potential to increase fertility. Metformin is an approved drug by FDA for diabetes and this study may add another potential clinical use for metformin.

The function of metformin in endometrial receptivity (ER) of patients with polycyclic ovary syndrome (PCOS): a systematic review and meta-analysis

BACKGROUND

This meta-analysis summarizes evidence from studies using metformin (Met) to improve endometrial receptivity (ER) in women with PCOS.

METHODS

Following the PRISMA protocol, we conducted a comprehensive search of academic literature from various databases, including PubMed, EMbase and Cochrane libraries. Studies published in English before Jan 27, 2021, were recruited for primary screening. Data on endometrial thickness (EMT), endometrial artery resistance index (RI), clinical pregnancy rate (CPR) and miscarriage rate (MR) were extracted and analyzed.

RESULTS

Sixty-two eligible studies that included 6571 patients were evaluated in this meta-analysis. Primary indicators are EMT and endometrial aetery RI; secondary indicators include the clinical pregnancy rate and miscarriage rate. Metformin significantly increased EMT (SMD = 2.04, 95% CI (0.96,3.12),P = 0.0002) and reduced endometrial artery RI compared to the non-Met group (SMD = - 2.83, 95% CI: (- 5.06, - 0.59), P = 0.01). As expected, metformin also improved CPR and reduced MR in PCOS patients as a result, clinical pregnancy rate (risk ratio [RR] = 1.26, 95% CI: 1.11-1.43, P = 0.0003), and miscarriage rate (RR = 0.73, 95% CI:0.58-0.91, P = 0.006).

CONCLUSION

Metformin may improve endometrial receptivity (ER) in PCOS patients by increasing EMT and reducing endometrial artery RI. However, the level of most original studies was low, with small sample sizes. More large-scale, long-term RCTs with rigorous methodologies are needed.

Molecular Mechanisms of Laparoscopic Ovarian Drilling and Its Therapeutic Effects in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrinopathy, characterized by chronic anovulation, hyperandrogenism, and multiple small subcapsular cystic follicles in the ovary during ultrasonography, and affects 5–10% of women of reproductive age. PCOS is frequently associated with insulin resistance (IR) accompanied by compensatory hyperinsulinemia and, therefore, presents an increased risk of type 2 diabetes mellitus (DM). The pathophysiology of PCOS is unclear, and many hypotheses have been proposed. Among these hypotheses, IR and hyperandrogenism may be the two key factors. The first line of treatment in PCOS includes lifestyle changes and body weight reduction. Achieving a 5–15% body weight reduction may improve IR and PCOS-associated hormonal abnormalities. For women who desire pregnancy, clomiphene citrate (CC) is the front-line treatment for ovulation induction. Twenty five percent of women may fail to ovulate spontaneously after three cycles of CC treatment, which is called CC-resistant PCOS. For CC-resistant PCOS women, there are many strategies to improve ovulation rate, including medical treatment and surgical approaches. Among the various surgical approaches, one particular surgical method, called laparoscopic ovarian drilling (LOD), has been proposed as an alternative treatment. LOD results in an overall spontaneous ovulation rate of 30–90% and final pregnancy rates of 13–88%. These benefits are more significant for women with CC-resistant PCOS. Although the intra- and post-operative complications and sequelae are always important, we believe that a better understanding of the pathophysiological changes and/or molecular mechanisms after LOD may provide a rationale for this procedure. LOD, mediated mainly by thermal effects, produces a series of morphological and biochemical changes. These changes include the formation of artificial holes in the very thick cortical wall, loosening of the dense and hard cortical wall, destruction of ovarian follicles with a subsequently decreased amount of theca and/or granulosa cells, destruction of ovarian stromal tissue with the subsequent development of transient but purulent and acute inflammatory reactions to initiate the immune response, and the continuing leakage or drainage of “toxic” follicular fluid in these immature and growth-ceased pre-antral follicles. All these factors contribute to decreasing local and systemic androgen levels, the following apoptosis process with these pre-antral follicles to atresia; the re-starting of normal follicular recruitment, development, and maturation, and finally, the normalization of the “hypothalamus–pituitary–ovary” axis and subsequent spontaneous ovulation. The detailed local and systematic changes in PCOS women after LOD are comprehensively reviewed in the current article.

Laparoscopic ovarian drilling for ovulation induction in women with anovulatory polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common condition affecting 8% to 13% of reproductive-aged women. In the past clomiphene citrate (CC) used to be the first-line treatment in women with PCOS. Ovulation induction with letrozole should be the first-line treatment according to new guidelines, but the use of letrozole is off-label. Consequently, CC is still commonly used. Approximately 20% of women on CC do not ovulate. Women who are CC-resistant can be treated with gonadotrophins or other medical ovulation-induction agents. These medications are not always successful, can be time-consuming and can cause adverse events like multiple pregnancies and cycle cancellation due to an excessive response. Laparoscopic ovarian drilling (LOD) is a surgical alternative to medical treatment. There are risks associated with surgery, such as complications from anaesthesia, infection, and adhesions.

OBJECTIVES

To evaluate the effectiveness and safety of LOD with or without medical ovulation induction compared with medical ovulation induction alone for women with anovulatory polycystic PCOS and CC-resistance.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Group (CGFG) trials register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL and two trials registers up to 8 October 2019, together with reference checking and contact with study authors and experts in the field to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of women with anovulatory PCOS and CC resistance who underwent LOD with or without medical ovulation induction versus medical ovulation induction alone, LOD with assisted reproductive technologies (ART) versus ART, LOD with second-look laparoscopy versus expectant management, or different techniques of LOD.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risks of bias, extracted data and evaluated the quality of the evidence using the GRADE method. The primary effectiveness outcome was live birth and the primary safety outcome was multiple pregnancy. Pregnancy, miscarriage, ovarian hyperstimulation syndrome (OHSS), ovulation, costs, and quality of life were secondary outcomes.

MAIN RESULTS

This updated review includes 38 trials (3326 women). The evidence was very low- to moderate-quality; the main limitations were due to poor reporting of study methods, with downgrading for risks of bias (randomisation and allocation concealment) and lack of blinding. Laparoscopic ovarian drilling with or without medical ovulation induction versus medical ovulation induction alone Pooled results suggest LOD may decrease live birth slightly when compared with medical ovulation induction alone (odds ratio (OR) 0.71, 95% confidence interval (CI) 0.54 to 0.92; 9 studies, 1015 women; I² = 0%; low-quality evidence). The evidence suggest that if the chance of live birth following medical ovulation induction alone is 42%, the chance following LOD would be between 28% and 40%. The sensitivity analysis restricted to only RCTs with low risk of selection bias suggested there is uncertainty whether there is a difference between the treatments (OR 0.90, 95% CI 0.59 to 1.36; 4 studies, 415 women; I² = 0%, low-quality evidence). LOD probably reduces multiple pregnancy rates (Peto OR 0.34, 95% CI 0.18 to 0.66; 14 studies, 1161 women; I² = 2%; moderate-quality evidence). This suggests that if we assume the risk of multiple pregnancy following medical ovulation induction is 5.0%, the risk following LOD would be between 0.9% and 3.4%. Restricting to RCTs that followed women for six months after LOD and six cycles of ovulation induction only, the results for live birth were consistent with the main analysis. There may be little or no difference between the treatments for the likelihood of a clinical pregnancy (OR 0.86, 95% CI 0.72 to 1.03; 21 studies, 2016 women; I² = 19%; low-quality evidence). There is uncertainty about the effect of LOD compared with ovulation induction alone on miscarriage (OR 1.11, 95% CI 0.78 to 1.59; 19 studies, 1909 women; I² = 0%; low-quality evidence). OHSS was a very rare event. LOD may reduce OHSS (Peto OR 0.25, 95% CI 0.07 to 0.91; 8 studies, 722 women; I² = 0%; low-quality evidence). Unilateral LOD versus bilateral LOD Due to the small sample size, the quality of evidence is insufficient to justify a conclusion on live birth (OR 0.83, 95% CI 0.24 to 2.78; 1 study, 44 women; very low-quality evidence). There were no data available on multiple pregnancy. The likelihood of a clinical pregnancy is uncertain between the treatments, due to the quality of the evidence and the large heterogeneity between the studies (OR 0.57, 95% CI 0.39 to 0.84; 7 studies, 470 women; I² = 60%, very low-quality evidence). Due to the small sample size, the quality of evidence is not sufficient to justify a conclusion on miscarriage (OR 1.02, 95% CI 0.31 to 3.33; 2 studies, 131 women; I² = 0%; very low-quality evidence). Other comparisons Due to lack of evidence and very low-quality data there is uncertainty whether there is a difference for any of the following comparisons: LOD with IVF versus IVF, LOD with second-look laparoscopy versus expectant management, monopolar versus bipolar LOD, and adjusted thermal dose versus fixed thermal dose.

AUTHORS' CONCLUSIONS

Laparoscopic ovarian drilling with and without medical ovulation induction may decrease the live birth rate in women with anovulatory PCOS and CC resistance compared with medical ovulation induction alone. But the sensitivity analysis restricted to only RCTs at low risk of selection bias suggests there is uncertainty whether there is a difference between the treatments, due to uncertainty around the estimate. Moderate-quality evidence shows that LOD probably reduces the number of multiple pregnancy. Low-quality evidence suggests that there may be little or no difference between the treatments for the likelihood of a clinical pregnancy, and there is uncertainty about the effect of LOD compared with ovulation induction alone on miscarriage. LOD may result in less OHSS. The quality of evidence is insufficient to justify a conclusion on live birth, clinical pregnancy or miscarriage rate for the analysis of unilateral LOD versus bilateral LOD. There were no data available on multiple pregnancy.

Metformin for ovulation induction (excluding gonadotrophins) in women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is characterised by infrequent or absent ovulation, and high levels of androgens and insulin (hyperinsulinaemia). Hyperinsulinaemia occurs secondary to insulin resistance and is associated with an increased biochemical risk profile for cardiovascular disease and an increased prevalence of diabetes mellitus. Insulin-sensitising agents such as metformin may be effective in treating PCOS-related anovulation. This is an update of Morley 2017 and only includes studies on metformin.

OBJECTIVES

To evaluate the effectiveness and safety of metformin in combination with or in comparison to clomiphene citrate (CC), letrozole and laparoscopic ovarian drilling (LOD) in improving reproductive outcomes and associated gastrointestinal side effects for women with PCOS undergoing ovulation induction.

SEARCH METHODS

We searched the following databases from inception to December 2018: Cochrane Gynaecology and Fertility Group Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO and CINAHL. We searched registers of ongoing trials and reference lists from relevant studies.

SELECTION CRITERIA

We included randomised controlled trials of metformin compared with placebo, no treatment, or in combination with or compared with CC, letrozole and LOD for women with PCOS subfertility.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for eligibility and bias. Primary outcomes were live birth rate and gastrointestinal adverse effects. Secondary outcomes included other pregnancy outcomes and ovulation. We combined data to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs). We assessed statistical heterogeneity using the I² statistic and reported quality of the evidence for primary outcomes and reproductive outcomes using GRADE methodology.

MAIN RESULTS

We included 41 studies (4552 women). Evidence quality ranged from very low to moderate based on GRADE assessment. Limitations were risk of bias (poor reporting of methodology and incomplete outcome data), imprecision and inconsistency. Metformin versus placebo or no treatment The evidence suggests that metformin may improve live birth rates compared with placebo (OR 1.59, 95% CI 1.00 to 2.51; I² = 0%; 4 studies, 435 women; low-quality evidence). For a live birth rate of 19% following placebo, the live birth rate following metformin would be between 19% and 37%. The metformin group probably experiences more gastrointestinal side effects (OR 4.00, 95% CI 2.63 to 6.09; I² = 39%; 7 studies, 713 women; moderate-quality evidence). With placebo, the risk of gastrointestinal side effects is 10% whereas with metformin this risk is between 22% and 40%. There are probably higher rates of clinical pregnancy (OR 1.98, 95% CI 1.47 to 2.65; I² = 30%; 11 studies, 1213 women; moderate-quality evidence). There may be higher rates of ovulation with metformin (OR 2.64, 95% CI 1.85 to 3.75; I² = 61%; 13 studies, 684 women; low-quality evidence). We are uncertain about the effect on miscarriage rates (OR 1.08, 95% CI 0.50 to 2.35; I² = 0%; 4 studies, 748 women; low-quality evidence). Metformin plus CC versus CC alone We are uncertain if metformin plus CC improves live birth rates compared to CC alone (OR 1.27, 95% CI 0.98 to 1.65; I² = 28%; 10 studies, 1219 women; low-quality evidence), but gastrointestinal side effects are probably more common with combined therapy (OR 4.26, 95% CI 2.83 to 6.40; I² = 8%; 6 studies, 852 women; moderate quality evidence). The live birth rate with CC alone is 24%, which may change to between 23% to 34% with combined therapy. With CC alone, the risk of gastrointestinal side effects is 9%, which increases to between 21% to 37% with combined therapy. The combined therapy group probably has higher rates of clinical pregnancy (OR 1.62, 95% CI 1.32 to 1.99; I² = 31%; 19 studies, 1790 women; moderate-quality evidence). The combined group may have higher rates of ovulation (OR 1.65, 95% CI 1.35 to 2.03; I² = 63%;21 studies, 1568 women; low-quality evidence). There was no clear evidence of an effect on miscarriage (OR 1.35, 95% CI 0.91 to 2.00; I² = 0%; 10 studies, 1206 women; low-quality evidence). Metformin versus CC When all studies were combined, findings for live birth were inconclusive and inconsistent (OR 0.71, 95% CI 0.49 to 1.01; I² = 86%; 5 studies, 741 women; very low-quality evidence). In subgroup analysis by obesity status, obese women had a lower birth rate in the metformin group (OR 0.30, 95% CI 0.17 to 0.52; 2 studies, 500 women), while the non-obese group showed a possible benefit from metformin, with high heterogeneity (OR 1.71, 95% CI 1.00 to 2.94; I² = 78%, 3 studies, 241 women; very low-quality evidence). However, due to the very low quality of the evidence we cannot draw any conclusions. Among obese women taking metformin there may be lower rates of clinical pregnancy (OR 0.34, 95% CI 0.21 to 0.55; I² = 0%; 2 studies, 500 women; low-quality evidence) and ovulation (OR 0.29, 95% CI 0.20 to 0.43; I² = 0%; 2 studies, 500 women; low-quality evidence) while among non-obese women, the metformin group may have more pregnancies (OR 1.56, 95% CI 1.06 to 2.29; I² = 26%; 6 studies, 530 women; low-quality evidence) and no clear difference in ovulation rates (OR 0.80, 95% CI 0.52 to 1.25; I² = 0%; 5 studies, 352 women; low-quality evidence). We are uncertain whether there is a difference in miscarriage rates between the groups (overall: OR 0.92, 95% CI 0.51 to 1.66; I² = 36%; 6 studies, 781 women; low-quality evidence) and no studies reported gastrointestinal side effects.

AUTHORS' CONCLUSIONS

Our updated review suggests that metformin may be beneficial over placebo for live birth however, more women probably experience gastrointestinal side effects. We are uncertain if metformin plus CC improves live birth rates compared to CC alone, but gastrointestinal side effects are probably increased with combined therapy. When metformin was compared with CC, data for live birth were inconclusive, and the findings were limited by lack of evidence. Results differed by body mass index (BMI), emphasising the importance of stratifying results by BMI. No studies reported gastrointestinal side effects in this comparison. Due to the low quality of the evidence, we are uncertain of the effect of metformin on miscarriage in all three comparisons.

Ovarian surgery for symptom relief in women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine condition, affecting approximately one in 10 women. PCOS is defined by two of three features: oligo- or anovulation, clinical or biochemical hyperandrogenism or both, or polycystic ovaries.Women with PCOS can have a wide range of health problems, including infrequent and irregular periods, unwanted hair growth and acne, and subnormal fertility. Long-term health concerns include an increased risk of heart disease, diabetes and the development of precancerous disease of the womb.

OBJECTIVES

To assess the effectiveness and harms of ovarian surgery as a treatment for symptomatic relief of hirsutism, acne and menstrual irregularity in PCOS.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Group specialized register, CENTRAL, MEDLINE, Embase and PsycINFO (from inception to 17 October 2016). We handsearched citation lists, registers of ongoing trials and conference proceedings.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of women undergoing ovarian drilling in comparison to no treatment, medical treatment, or other forms of surgical treatment for the symptoms of PCOS.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. The primary outcome measures were improvement in menstrual regularity and androgenic symptoms of PCOS (hirsutism, acne); the secondary outcome measures included harms, change of body mass index (BMI), waist circumference, androgen levels, metabolic measures and quality of life. We assessed the quality of the evidence using GRADE methods.

MAIN RESULTS

We included 22 RCTs (2278 women analyzed) of participants with PCOS and symptoms of acne, hirsutism or irregular menstrual cycles, all of which included laparoscopic ovarian drilling (LOD) as an intervention.Two studies reported their funding source (Farquhar 2002 - supported in part by the Auckland Medical Research Foundation; Sarouri 2015 - the authors thank the Vice Chancellor for Research of Guilan University of Medical Sciences for funding this project).The quality of the evidence ranged from very low to moderate quality. The main limitations were imprecision associated with the low number of studies, inconsistency and risk of bias associated with the inability to blind participants. There were too few studies to assess risk of publication bias. Menstrual RegularityTwo studies compared LOD versus metformin (n=226) but no conclusions could be drawn with regard to menstrual regularity, as their findings were inconsistent and they were unsuitable for pooling. There appeared to be little or no difference in the rate of women reporting improvement in menstrual regularity when LOD was compared with medical treatment including metformin + clomiphene (OR 1.02, 95% CI 0.64 to 1.64, 2 studies, 332 women, I² = 13%, low-quality evidence), letrozole (OR 1.08, 95% CI 0.64 to 1.84, 1 study, 260 women, low-quality evidence), or metformin + letrozole (OR 0.95, 95% CI 0.49 to 1.81, 1 study, 146 women, low-quality evidence). However, one study reported that LOD was superior to gonadotrophin (OR 19.2, 95% CI 3.17 to 116.45, 1 study, 35 women, very low-quality evidence).There appeared to be little or no difference in the rate of women reporting improvement in menstrual regularity when bilateral unipolar LOD was compared to unilateral LOD (OR 1.51, 95% CI 0.62 to 3.71, 2 studies, 104 women, I² = 0%, moderate-quality evidence), transvaginal ultrasound-guided LOD (OR 1.23, 95% CI 0.64 to 2.37, 1 study, 147 women, low-quality evidence), LOD using adjusted thermal dose in accordance with the ovarian volume (OR 0.42, 95% CI 0.16 to 1.14, 1 study, 115 women, low-quality evidence) or bipolar LOD (OR 1.00, 95% CI 0.05 to 18.57, 1 study, 18 women, low-quality evidence).Four to five punctures per ovary may improve the rate of women reporting menstrual regularity compared with two or fewer (OR 16.04, 95% CI 4.19 to 61.34, 2 studies, 73 women, I² = 0%, low-quality evidence). Androgenic SymptomsThere was probably little or no difference in improvement in androgenic symptoms when LOD was compared to metformin (OR 1.00, 95% CI 0.42 to 2.37, 1 study, 126 women, moderate-quality evidence) or gonadotrophins; acne (OR 3.20, 95% CI 0.33 to 30.94, 1 study, 25 women, low-quality evidence), hirsutism (OR 2.31, 95% CI 0.22 to 23.89, 1 study, 25 women, low-quality evidence).There appeared to be little or no difference in improvement of androgenic symptoms when LOD was compared to transvaginal ultrasound-guided LOD, with respect to hirsutism (OR 1.09, 95% CI 0.30 to 3.91, 1 study, 39 women, low-quality evidence) or acne (OR 0.84, 95% CI 0.20 to 3.50, 1 study, 31 women, low-quality evidence). HarmsLOD was associated with fewer gastrointestinal side effects than metformin plus clomiphene (OR 0.05, 95% CI 0.01 to 0.36, 2 studies, 332 women, I² = 0%, moderate-quality evidence). One study suggested little or no difference in rates of ovarian hyperstimulation syndrome between LOD and gonadotrophins (OR 0.08, 95% CI 0.00 to 1.61, 1 study, 33 women, low-quality evidence).There were fewer adhesions with transvaginal hydrolaparoscopy compared to LOD (OR 0.10, 95% CI 0.05 to 0.18, 1 study, 246 women, moderate-quality evidence). There appeared to be little or no difference in adhesions when variable energy LOD was compared with standard LOD (OR 0.96, 95% CI 0.32 to 2.88, 1 study, 64 women, low-quality evidence). Another study (44 women) reported that none of the women who returned for surgery following either traditional or unilateral LOD were found to have adhesions.

AUTHORS' CONCLUSIONS

There was no clear evidence that LOD improves menstrual regularity or the androgenic symptoms of PCOS, compared to most of the medical treatments used in the included studies. LOD was associated with fewer gastrointestinal side effects compared to metformin and clomiphene.There was also no clear evidence of different effectiveness between types of LOD, except that LOD with four to five punctures per ovary may be more effective than two or fewer punctures. There was little evidence comparing LOD with different types of surgery, although one study concluded that transvaginal hydrolaparoscopy had a lower risk of adhesions than LOD.There was evidence from one small study of benefit from LOD compared to gonadotrophins for menstrual regulation. However, gonadotrophins are seldom used for this indication.

Comparative effectiveness of 9 ovulation-induction therapies in patients with clomiphene citrate-resistant polycystic ovary syndrome: a network meta-analysis

The comparative efficacies of ovulation-induction treatments in patients with clomiphene citrate-resistant (CCR) polycystic ovary syndrome (PCOS) are not well known. Therefore, we conducted a network meta-analysis to rank the reproductive efficacies of these treatments. We ultimately included 26 randomized clinical trials with 2722 participants and 9 types of therapies: clomiphene citrate (CC), metformin, letrozole, follicle stimulating hormone (FSH), human menopausal gonadotropin (hMG), unilateral laparoscopic ovarian drilling (ULOD), bilateral laparoscopic ovarian drilling (BLOD), the combination of metformin with letrozole (metformin+letrozole), and the combination of metformin with CC (metformin+CC). The network meta-analysis demonstrates that hMG therapy result in higher pregnancy rates than BLOD, ULOD and CC therapies. Pregnancy, live birth and ovulation rates are significantly higher in metformin+letrozole and FSH groups than CC group. The abortion rate in the metformin+letrozole group is significantly lower than that in the metformin+CC group. Ranking probabilities show that, apart from gonadotropin (FSH and hMG), metformin+letrozole is also potentially more effective in improving reproductive outcomes than other therapies. In conclusion, owing to the low quality of evidence and the wide confidence intervals, no recommendation could be made for the treatment of ovulation-induction in patients with CCR PCOS.

Laparoscopic ovarian drilling: An alternative but not the ultimate in the management of polycystic ovary syndrome

Since its introduction in 1984, laparoscopic ovarian drilling has evolved into a safe and effective surgical treatment for anovulatory, infertile women with polycystic ovary syndrome (PCOS), unresponsive to clomiphene citrate. It is as effective as gonadotropins in terms of pregnancy and live birth rates, but without the risks of ovarian hyperstimulation syndrome and multiple pregnancies. It improves ovarian responsiveness to successive ovulation induction agents. Its favorable reproductive and endocrinal effects are sustained long. Despite its advantages, its use in unselected cases of PCOS or for non-fertility indications is not prudent owing to the potential risks of iatrogenic adhesions and ovarian insufficiency.

Direct effects of metformin in the endometrium: a hypothetical mechanism for the treatment of women with PCOS and endometrial carcinoma

Although a number of in vitro studies have demonstrated the antiproliferative, anti-invasive, and antimetastatic effects of metformin in multiple cancer cell types, its cellular and molecular mechanisms of anti-cancer action in the endometrium of women with polycystic ovary syndrome (PCOS) have not yet been fully elucidated. Organic cation transporters (OCTs) and multidrug and toxin extrusion proteins (MATEs) are known to be involved in metformin uptake and excretion in cells. In this article, we discuss the novel therapeutic possibilities for early-stage endometrial carcinoma (EC) in women with PCOS focusing on metformin, which might have a direct effect in the endometrium through the OCTs and MATEs. We then review the molecular mechanism(s) of the action of metformin in the endometrium and highlight possible mechanistic insights into the inhibition of cell proliferation and tumor growth and, ultimately, the reversal of early-stage EC into normal endometria in women with PCOS.

Efficacy of combined metformin-letrozole in comparison with bilateral ovarian drilling in clomiphene-resistant infertile women with polycystic ovarian syndrome

OBJECTIVES

To compare the hormonal-metabolic profiles and reproductive outcomes between women receiving metformin plus letrozole and women undergoing bilateral ovarian drilling in clomiphene citrate (CC)-resistant women with polycystic ovary syndrome (PCOS).

METHODS

In this randomized study, 146 patients were randomly allocated into group 1 (n = 73) who received metformin plus letrozole, and group 2 (n = 73) who underwent bilateral ovarian drilling. Comparison was done between the basal and after treatment biochemical values for each group, in addition reproductive outcomes after treatment were compared between both groups.

RESULTS

There was significant reduction in testosterone (p ≤ 0.001), fasting insulin (p ≤ 0.001), and fasting glucose/fasting insulin ratio (p = 0.029) in metformin plus letrozole group, while there was significant reduction in FSH, LH and LH/FSH ratio in bilateral drilling group (p ≤ 0.001, 0.001 and 0.001). No significant difference in cycle regularity (p = 0.82), ovulation (p = 0.24), pregnancy rate (p = 0.32) and abortion rate (p = 0.51) between both groups.

CONCLUSION

Both metformin plus letrozole and bilateral ovarian drilling are similarly effective as second-line strategies for the treatment of women with PCOS who do not conceive with CC.

Laparoscopic drilling by diathermy or laser for ovulation induction in anovulatory polycystic ovary syndrome

BACKGROUND

Surgical ovarian wedge resection was the first established treatment for women with anovulatory polycystic ovary syndrome (PCOS) but was largely abandoned both due to the risk of postsurgical adhesions and the introduction of medical ovulation induction. However, women with PCOS who are treated with medical ovulation induction, with drugs such as gonadotrophins, often have an over-production of follicles which may result in ovarian hyperstimulation syndrome and multiple pregnancies. Moreover, gonadotrophins, though effective, are costly and time-consuming and their use requires intensive monitoring. Surgical therapy with laparoscopic ovarian 'drilling' (LOD) may avoid or reduce the need for medical ovulation induction, or may facilitate its usefulness. The procedure can be done on an outpatient basis with less trauma and fewer postoperative adhesions than with traditional surgical approaches. Many uncontrolled observational studies have claimed that ovarian drilling is followed, at least temporarily, by a high rate of spontaneous ovulation and conception, or that subsequent medical ovulation induction becomes easier.

OBJECTIVES

To determine the effectiveness and safety of laparoscopic ovarian drilling compared with ovulation induction for subfertile women with clomiphene-resistant PCOS.

SEARCH METHODS

We used the search strategy of the Menstrual Disorders and Subfertility Group (MDSG) to search the MDSG Trials Register, CENTRAL, MEDLINE, EMBASE, CINAHL and PsycINFO. The keywords included polycystic ovary syndrome, laparoscopic ovarian drilling, electrocautery and diathermy. Searches were conducted in September 2011, and a further search of the MDSG Trials Register was made on 14 May 2012.

SELECTION CRITERIA

We included randomised controlled trials of subfertile women with clomiphene-resistant PCOS who undertook laparoscopic ovarian drilling in order to induce ovulation.

DATA COLLECTION AND ANALYSIS

This is an update of a previously updated review. There were nine RCTs in the previous version; an additional 16 trials were added in the current (2012) update. All trials were assessed for quality. The primary outcomes were live birth and multiple pregnancy. The secondary outcomes were rate of miscarriage, ovulation and pregnancy rates, ovarian hyperstimulation syndrome (OHSS), quality of life and cost.

MAIN RESULTS

Nine trials, including 1210 women, reported on the primary outcome of live birth rate per couple. Live births were reported in 34% of women in the LOD groups and 38% in other medical treatment groups. There were five different comparisons with LOD and there was no evidence of a difference in live births when compared with clomiphene citrate + tamoxifen (OR 0.81; 95% CI 0.42 to 1.53; P = 0.51, 1 trial, n = 150), gonadotrophins (OR 0.97; 95% CI 0.59 to 1.59; P = 0.89, I(2) = 0%, 2 trials, n = 318), aromatase inhibitors (OR 0.84; 95% CI 0.54 to 1.31; P = 0.44, I(2) = 0%, 2 trials, n = 407) or clomiphene citrate (OR 1.21; 95%CI 0.64 to 2.32; 1 trial, n=176, P= 0.05). There was evidence of significantly fewer live births following LOD compared with clomiphene citrate + metformin (OR 0.44; 95% CI 0.24 to 0.82; P = 0.01, I(2) = 78%, 2 trials, n = 159); the high heterogeneity in this subgroup could not be explained by population differences or differences in quality of the trials.Thirteen trials reported on multiple pregnancies (n= 1305 women). There were no cases of multiple pregnancies in either group for clomiphene citrate or aromatase inhibitors compared with LOD. The rate of multiple pregnancies was significantly lower in the LOD group compared with trials using gonadotrophins (OR 0.13; 95% CI 0.03 to 0.52; P=0.004, I(2) = 0%, 5 trials, n = 166).

AUTHORS' CONCLUSIONS

There was no evidence of a significant difference in rates of clinical pregnancy, live birth or miscarriage in women with clomiphene-resistant PCOS undergoing LOD compared to other medical treatments. The reduction in multiple pregnancy rates in women undergoing LOD makes this option attractive. However, there are ongoing concerns about the long-term effects of LOD on ovarian function.

Impact of obesity on reproductive outcomes after ovarian ablative therapy in PCOS: a collaborative meta-analysis

Obesity is known to interfere with reproductive outcomes in polycystic ovary syndrome. There is no consensus regarding the impact of obesity on reproductive outcomes after ovarian ablative therapy (OAT) and there is no level I evidence to answer this question. This systematic review and meta-analysis assessed the strength of the association between obesity and ovulation or pregnancy rates after OAT. MEDLINE and several other databases were searched from 2000 to September 2011 for studies reporting on OAT and reproductive outcomes. Data were synthesized to determine the relative risk of reproductive outcomes (ovulation and pregnancy) in lean (body mass index <25 kg/m(2)) compared with overweight or obese women. The study obtained 15 data sets (14 articles) for analysis, which included 905 subjects in the obese group and 879 subjects in the lean group. Lean women had increased ovulation rates (RR 1.43, 95% CI 1.22-1.66) compared with obese women. Pregnancy rates also showed a similar trend (RR 1.73, 95% CI 1.39-2.17). Reproductive outcomes were generally better in younger women, more recent studies and randomized controlled trials. It is concluded that lean women respond better to OAT than their obese counterparts. These epidemiological observations indicate that obesity alters reproductive outcomes after OAT negatively. Obesity is known to interfere with reproductive outcomes in polycystic ovary syndrome. There is no consensus regarding the impact of obesity on ovarian ablative therapy (OAT) and there is no level I evidence to answer this question. We therefore undertook a systematic review and meta-analysis to assess the strength of the association between obesity and ovulation or pregnancy rates after OAT. We searched MEDLINE and several other databases from 2000 to September 2011 for studies reporting on OAT and reproductive outcomes. Data were synthesized to determine the risk ratio of reproductive outcomes (ovulation and pregnancy) in lean (BMI <25 kg/m(2)) as opposed to overweight or obese women. We obtained 15 datasets (14 articles) for analysis, which included 905 subjects in the obese group and 879 subjects in the lean group. Lean women had increased ovulation rates (RR 1.43, 95% CI 1.22-1.66) as compared to obese women. Pregnancy rates also showed a similar trend (RR 1.73, 95% CI 1.39-2.17). Reproductive outcomes were generally better in younger women, more recent studies and randomized controlled trials. We conclude that lean women respond better to OAT than their obese counterparts. These epidemiological observations indicate that obesity alters reproductive outcomes after OAT negatively.