Randomized controlled trial of the effects of metformin versus combined oral contraceptives in adolescent PCOS women through a 24month follow up period

Metformin use in women with polycystic ovary syndrome (PCOS): Opportunities, benefits, and clinical challenges

Metformin, a synthetic biguanide, is widely used to manage type 2 diabetes, and is commonly prescribed in polycystic ovary syndrome (PCOS) to address insulin resistance and associated metabolic and reproductive disturbances. PCOS is characterised by hormonal imbalances such as hyperandrogenism and anovulation, metabolic abnormalities including insulin resistance and increased cardiometabolic risk, and higher rates of pregnancy complications. However, the role of metformin in the multifaceted nature of PCOS remains debated. This review synthesises the mechanisms of action of metformin and its effects on metabolic, hormonal, reproductive, and pregnancy-related outcomes in PCOS. In non-pregnant women, metformin improves insulin resistance, menstrual regularity, and androgen levels, particularly in those with obesity or insulin resistance, and may enhance fertility when combined with other treatments. However, it is not effective as a first-line therapy for weight loss, ovulation induction, or treatment of clinical hyperandrogenic features, including hirsutism or acne. In pregnancy, metformin may reduce early pregnancy loss, miscarriage, and preterm birth, though findings for gestational diabetes and preeclampsia are inconsistent. Evidence is limited by study heterogeneity, varying diagnostic criteria, and the use of aggregate data in meta-analyses, all of which make interpretation challenging. Future research should prioritise well-powered clinical trials, individual patient data meta-analyses, and longer-term follow-up studies, particularly in pregnancy, to better define the populations most likely to benefit from metformin use across the PCOS spectrum. PLAIN LANGUAGE SUMMARY: Polycystic ovary syndrome (PCOS) is a common condition that affects up to 1 in 10 women of reproductive age. It is characterised by irregular or absent periods, signs of elevated male hormones (high androgens or excess hair growth), and/or polycystic ovaries seen on ultrasound. These features can lead to fertility problems, acne, psychological distress, and an increased risk of various disorders such as depression, type 2 diabetes and heart disease. Many women with PCOS also experience challenges during pregnancy, including a higher risk of miscarriage, preterm birth, and gestational diabetes. Metformin is a medication most often used to manage diabetes. In women with PCOS, it can help improve how the body responds to insulin, which may also reduce male hormone levels, improve menstrual cycles, and support fertility. This review examines the role of metformin in treating PCOS-both before and during pregnancy-by summarising key findings from the available evidence. In women who are not pregnant, metformin can help improve insulin resistance, hormone levels, and menstrual regularity, particularly among those who are overweight or have signs of insulin resistance. However, metformin alone is not a first-choice treatment for weight loss, ovulation problems, or symptoms such as acne and unwanted hair growth. When combined with other treatments, such as hormone therapy or fertility medications, it may offer additional benefits. During pregnancy, metformin is considered safe for use in women with PCOS and may lower the risk of early pregnancy loss and preterm birth. However, its effects on preventing gestational diabetes or high blood pressure are less clear, with mixed results across studies. Some research suggests that babies exposed to metformin in the womb may have slightly larger head sizes or a higher risk of being overweight in early childhood, but the long-term health effects remain unknown. Overall, metformin can be a helpful part of treatment for some women with PCOS, especially those with insulin resistance or certain pregnancy risks. Still, it is not a one-size-fits-all solution. More high-quality research is needed to better understand which women benefit most and to assess any long-term effects on children exposed to metformin during pregnancy.

Metformin and Combined Oral Contraceptive Pills in the Management of Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis

CONTEXT

Polycystic ovary syndrome (PCOS) affects more than 1 in 10 women.

OBJECTIVE

As part of the 2023 International PCOS Guidelines update, comparisons between combined oral contraceptive pills (COCP), metformin, and combination treatment were evaluated.

DATA SOURCES

Ovid Medline, Embase, PsycINFO, All EBM, and CINAHL were searched.

STUDY SELECTION

Women with PCOS included in randomized controlled trials (RCTs).

DATA EXTRACTION

We calculated mean differences and 95% CIs regarding anthropometrics, metabolic, and hyperandrogenic outcomes. Meta-analyses and quality assessment using GRADE were performed.

DATA SYNTHESIS

The search identified 1660 publications; 36 RCTs were included. For hirsutism, no differences were seen when comparing metformin vs COCP, nor when comparing COCP vs combination treatment with metformin and COCP. Metformin was inferior on free androgen index (FAI) (7.08; 95% CI 4.81, 9.36), sex hormone binding globulin (SHBG) (-118.61 nmol/L; 95% CI -174.46, -62.75) and testosterone (0.48 nmol/L; 95% CI 0.32, 0.64) compared with COCP. COCP was inferior for FAI (0.58; 95% CI 0.36, 0.80) and SHBG (-16.61 nmol/L; 95% CI -28.51, -4.71) compared with combination treatment, whereas testosterone did not differ. Metformin lowered insulin (-27.12 pmol/L; 95% CI -40.65, -13.59) and triglycerides (-0.15 mmol/L; 95% CI -0.29, -0.01) compared with COCP. COCP was inferior for insulin (17.03 pmol/L; 95% CI 7.79, 26.26) and insulin resistance (0.44; 95% CI 0.17, 0.70) compared with combination treatment.

CONCLUSIONS

The choice of metformin or COCP treatment should be based on symptoms, noting some biochemical benefits from combination treatment targeting both major endocrine disturbances seen in PCOS (hyperinsulinemia and hyperandrogenism).

SGLT-2 inhibitors enhance the effect of metformin to ameliorate hormonal changes and inflammatory markers in a rat PCOS model

Polycystic ovary syndrome (PCOS) is a common endocrine, reproductive, and metabolic disorder affecting females. The management of PCOS is challenging and current interventions are not enough to deal with all consequences of this syndrome. We explored the beneficial effect of combined sodium glucose co transporter-2 inhibitor (SGLT-2i); (empagliflozin) and metformin on hormonal and metabolic parameters in an animal model of PCOS and insulin resistance (IR). Forty adult female Wistar rats divided into five groups: control, PCOS-IR, PCOS-IR treated with metformin, PCOS-IR treated with empagliflozin, and PCOS-IR treated with combined metformin and empagliflozin. Single modality treatment with metformin or empagliflozin yielded significant improvement in body mass index, insulin resistance, lipid profile, sex hormones, inflammatory markers, and ovarian cystic follicles. Combined metformin with empagliflozin expressed further significant improvement in sex hormones, inflammatory markers with disappearance of ovarian cystic follicles. The superior significant improvement with combined treatment over the single modality was in line with significant improvement in the ovarian AMPKα-SIRT1 expression.

Combined oral contraceptive pill compared with no medical treatment in the management of polycystic ovary syndrome: A systematic review

OBJECTIVE

As part of the update of the International Evidence-Based Guidelines for the Assessment and Management of polycystic ovary syndrome (PCOS), a systematic review was performed to inform evidence-based recommendations.

DESIGN

Systematic review. Only randomised controlled trial were included.

PATIENTS

Women with PCOS; the use of combined oral contraceptive pills (COCP) was compared with no medical treatment.

MEASUREMENTS

Outcomes were designed in collaboration with clinical experts, researchers, and consumers. Critical outcomes included hirsutism, irregular cycles, quality of life, body mass index (BMI), and weight.

RESULTS

1660 publications were identified, but only four studies were included. No studies could be combined for meta-analysis. COCP treatment improved cycle regularity compared with no medical treatment (100% vs. 0%, with low certainty of evidence). COCP showed no difference in improvement of hirsutism or BMI compared with placebo or lifestyle; a lower weight after COCP compared with no treatment (mean difference [MD] -8.0 (95% confidence interval, CI -11.67); -4.33 kg); and improvement in quality of life (MD 1.2 [95% CI 0.96]; 1.44), but these results were all very low certainty of evidence.

CONCLUSION

Results show that COCP benefit cycle regulation, but other benefits or potential adverse effects were only identified with very low certainty of evidence. The COCP is frontline medical treatment in PCOS, but this is still based on established efficacy in the broader general population. Our results show that research in PCOS is seriously lacking and should be prioritised to capture core reproductive, metabolic and psychological outcomes important in PCOS.

Non-Hormonal Treatment Options for Regulation of Menstrual Cycle in Adolescents with PCOS

Menstrual irregularities are one of the main clinical symptoms caused by polycystic ovary syndrome (PCOS). Pharmacological treatment options for non-fertility indications to restore menstrual frequency play an important role in the management of PCOS. Oral contraceptive pills are commonly prescribed for adolescents with menstrual irregularities, however, when contraindicated or poorly tolerated, further pharmacological therapy is required. This systematic literature research aims to provide an overview concerning the effects of non-hormonal pharmacological treatment options on menstrual irregularities in adolescents suffering from PCOS. A systematic literature search in PubMed, Cochrane, Embase, Bio-SISS and Web of Science was performed, including literature from January 1998 to September 2022, using specific keywords in order to find related studies. n = 265 studies were identified of which n = 164 were eligible for further evaluation. Only four placebo-controlled studies were identified, with diverging inclusion and exclusion criteria. Available data on specific non-hormonal off-label use medication primarily consisted of metformin, Glucagon-like peptide 1 receptor agonists, thiazolidinediones, anti-androgen agents (spironolactone, finasteride, flutamide) and supplements (chromium picolinate, myo-inositol). However, only a few have partly pointed out beneficial effects on improving menstrual frequency in patients diagnosed with PCOS. In summary, metformin in dosages of 1500-2550 g/day, GLP-1-analogues and supplements were effective in regulation of menstrual cycles in adolescents diagnosed with PCOS. Menstrual frequency in adolescents with PCOS is essential to prevent hypoestrogenism with long-term consequences. In this context, MET is the most effective and cost- efficient in overweight adolescent girls, also showing beneficial effects in the regulation of insulin sensitivity, especially if COCs are contraindicated or not well-tolerated. Further studies are needed to evaluate therapies in lean and normal-weight girls with PCOS.

Metformin therapy in pediatric type 2 diabetes mellitus and its comorbidities: A review

Type 2 diabetes (T2D) rates in children and adolescents are rising globally. T2D is a complex and aggressive disease in children with several comorbidities, high treatment failure rates, and insulin needs within a few years from diagnosis. While myriads of pharmacotherapies are licensed to treat adults with T2D, treatments accessible to children and adolescents have been limited until recently. Metformin is an old drug with multiple beneficial metabolic health effects beyond glycemic control. This review discusses Metformin's origins, its mechanisms of action, and evidence for its use in the pediatric population to treat and prevent T2D. We also explore the evidence for its use as an obesity therapy, which is the primary driver of T2D, and T2D-driven comorbidities. While emerging therapies create new horizons for managing pediatric T2D, Metformin remains an inexpensive and safe part of the treatment plans of many T2D children globally for its beneficial metabolic effects.

Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in polycystic ovary syndrome

BACKGROUND

Metformin has been proposed as possibly a safer and more effective long-term treatment than the oral contraceptive pill (OCP) in women with polycystic ovary syndrome (PCOS). It is important to directly compare the efficacy and safety of metformin versus OCP in the long-term treatment of women with PCOS. This is an update of a Cochrane Review comparing insulin sensitising agents with the OCP and only includes studies on metformin.

OBJECTIVES

To assess the effectiveness and safety of metformin versus the OCP (alone or in combination) in improving clinical, hormonal, and metabolic features of PCOS.

SEARCH METHODS

In August 2019 we searched the Cochrane Gynaecology and Fertility Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and CINAHL, the trial registers, handsearched references of the identified articles, and contacted experts in the field to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of the use of metformin versus the OCP (alone or in combination) for women with PCOS.

DATA COLLECTION AND ANALYSIS

We used standard methods recommended by Cochrane. The primary review outcomes were the clinical parameters of hirsutism and adverse events, both severe (requiring stopping of medication), and minor. In the presence of substantial heterogeneity (I2 statistic > 50), which could be explained by pre-specified subgroup analyses on the basis of BMI, we reported the subgroups separately.

MAIN RESULTS

This is a substantive update. We identified 38 additional studies. We included 44 RCTs (2253 women), which comprised 39 RCTs on adult women (2047 women) and five RCTs on adolescent women (206 women). Evidence quality ranged from very low to low. The main limitations were risk of bias, imprecision and inconsistency. Metformin versus the OCP In adult women, we are uncertain of the effect of metformin compared to the OCP on hirsutism in subgroup body mass index (BMI) < 25 kg/m2 (mean difference (MD) 0.38, 95% confidence interval (CI) -0.44 to 1.19, 3 RCTs, n = 134, I2 = 50%, very low-quality evidence) and subgroup BMI > 30 kg/m2 (MD -0.38, 95% CI -1.93 to 1.17; 2 RCTs, n = 85, I2 = 34%, low-quality evidence). Metformin may be less effective in improving hirsutism compared to the OCP in the subgroup BMI 25 kg/m2 to 30 kg/m2 (MD 1.92, 95% CI 1.21 to 2.64, 5 RCTs, n = 254, I2 = 0%, low-quality evidence). Metformin may increase severe gastro-intestinal adverse events rate compared to the OCP (Peto odds ratio (OR) 6.42, 95% CI 2.98 to 13.84, 11 RCTs, n = 602, I2 = 0%, low-quality evidence). Metformin may decrease the incidence of severe other adverse events compared to the OCP (Peto OR 0.20, 95% CI 0.09 to 0.44, 8 RCTs, n = 363, I2 = 0%, low-quality evidence). There were no trials reporting on minor adverse events. In adolescents, we are uncertain whether there is a difference between Metformin and the OCP, on hirsutism and adverse events. Metformin versus metformin combined with the OCP In adult women, metformin may be less effective in improving hirsutism compared to Metformin combined with the OCP (MD 1.36, 95% CI 0.62 to 2.11, 3 RCTs, n = 135, I2= 9%, low-quality evidence). We are uncertain if there was a difference between metformin and metformin combined with the OCP for severe gastro-intestinal adverse events (OR 0.74, 95% CI 0.21 to 2.53, 3 RCTs, n = 171, I2 = 0%, low-quality evidence), or for severe other adverse events (OR 0.56, 95% CI 0.11 to 2.82, 2 RCTs, n = 109, I2 = 44%, low-quality evidence). There were no trials reporting on minor adverse events. In adolescents, there were no trials for this comparison. The OCP versus metformin combined with the OCP In adult women, the OCP may be less effective in improving hirsutism compared to metformin combined with the OCP (MD 0.54, 95% CI 0.20 to 0.89, 6 RCTs, n = 389, I2= 1%, low-quality evidence). The OCP may decrease the incidence of severe gastro-intestinal adverse events compared to metformin combined with the OCP (OR 0.20, 95% CI 0.06 to 0.72, 5 RCTs, n = 228, I2 = 0%, low-quality evidence). We are uncertain if there is a difference between the OCP and metformin combined with the OCP for severe other adverse events (OR 1.61, 95% CI 0.49 to 5.37, 4 RCTs, n = 159, I2 = 12%, low-quality evidence). The OCP may decrease the incidence of minor (gastro-intestinal) adverse events compared to metformin combined with the OCP (OR 0.06, 95% CI 0.01 to 0.44, 2 RCTs, n = 98, I2 = 0%, low-quality evidence). In adolescents, we are uncertain whether there is a difference between the OCP, compared to metformin combined with the OCP, on hirsutism or adverse events.

AUTHORS' CONCLUSIONS

In adult women with PCOS, metformin may be less effective in improving hirsutism compared to the OCP in the subgroup BMI 25 kg/m2 to 30 kg/m2 but we are uncertain if there was a difference between metformin and the OCP in subgroups BMI < 25 kg/m2 and BMI > 30kg/m2. Compared to the OCP, metformin may increase the incidence of severe gastro-intestinal adverse events and decrease the incidence of severe other adverse events with no trials reporting on minor adverse events. Either metformin alone or the OCP alone may be less effective in improving hirsutism compared to metformin combined with the OCP. We are uncertain whether there is a difference between the OCP alone and metformin alone compared to metformin combined with the OCP for severe or minor adverse events except for the OCP versus metformin combined with the OCP where the OCP may decrease the incidence of severe and minor gastro-intestinal adverse events. In adolescent women with PCOS, we are uncertain whether there is a difference between any of the comparisons for hirsutism and adverse events due to either no evidence or very low-quality evidence. Further large well-designed RCTs that stratify for BMI are needed to evaluate metformin versus the OCP and combinations in women with PCOS, in particular adolescent women.

Effect of lifestyle modifications on anthropometric, clinical, and biochemical parameters in adolescent girls with polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of childbearing age. This study aimed to compare the effects of lifestyle interventions on anthropometric, clinical, and biochemical parameters in adolescent girls with PCOS.

METHODS

PubMed, Scopus, and Web of Science was systematically searched to retrieve studies investigating the effects of lifestyle modifications in adolescent girls with PCOS, which were published up to December 2019. The primary outcome was Body Mass Index (BMI) and secondary outcomes were all manifestations of PCOS, including clinical, metabolic, and hormonal parameters. Random effect meta-analysis was applied for significant results. Publication bias was assessed using the Egger test.

RESULTS

This study showed significant improvements in luteinizing hormone (LH) (Pooled SMD = - 0.1.23; 95% CI, - 2.44 to - 0.03), and Free Androgen Index (FAI) levels (Pooled SMD = - 0.78 95% CI, - 0.1.42 to - 0.13) in adolescent girls receiving lifestyle intervention compared to baseline. This study also revealed that diet modifications alone were associated with a significant decrease in Body Mass Index (BMI) (Pooled SMD = - 0.45; 95% CI, - 0.76 to - 0.13), and FG score (Pooled SMD = - 0.81; 95% CI, - 1.33 to - 0.28). Exercise interventions were associated with significant changes in the menstrual cycles (Pooled SMD = 1.16; 95% CI, 0.72 to 1.61), Ferriman-Gallwey (FG) score (Pooled SMD = - 0.57; 95% CI, - 0.99 to - 0.15), LH (Pooled SMD = - 056; 95% CI, - 0.98 to - 0.14), Anti-Müllerian Hormone (AMH) (Pooled SMD = - 0.81; 95% CI, - 0.1.24 to - 0.38), and Triglyceride (TG) levels (Pooled SMD = - 0.32; 95% CI, - 0.62 to - 0.02).

CONCLUSION

This meta-analysis concluded lifestyle interventions, such as diet and exercise, can improve some clinical, metabolic, and hormonal parameters in adolescent girls with PCOS.

Adolescent polycystic ovary syndrome according to the international evidence-based guideline

BACKGROUND

Diagnosing polycystic ovary syndrome (PCOS) during adolescence is challenging because features of normal pubertal development overlap with adult diagnostic criteria. The international evidence-based PCOS Guideline aimed to promote accurate and timely diagnosis, to optimise consistent care, and to improve health outcomes for adolescents and women with PCOS.

METHODS

International healthcare professionals, evidence synthesis teams and consumers informed the priorities, reviewed published data and synthesised the recommendations for the Guideline. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework was applied to appraise the evidence quality and the feasibility, acceptability, cost, implementation and strength of the recommendations.

RESULTS

This paper focuses on the specific adolescent PCOS Guideline recommendations. Specific criteria to improve diagnostic accuracy and avoid over diagnosis include: (1) irregular menstrual cycles defined according to years post-menarche; > 90 days for any one cycle (> 1 year post-menarche), cycles< 21 or > 45 days (> 1 to < 3 years post-menarche); cycles < 21 or > 35 days (> 3 years post-menarche) and primary amenorrhea by age 15 or > 3 years post-thelarche. Irregular menstrual cycles (< 1 year post-menarche) represent normal pubertal transition. (2) Hyperandrogenism defined as hirsutism, severe acne and/or biochemical hyperandrogenaemia confirmed using validated high-quality assays. (3) Pelvic ultrasound not recommended for diagnosis of PCOS within 8 years post menarche. (4) Anti-Müllerian hormone levels not recommended for PCOS diagnosis; and (5) exclusion of other disorders that mimic PCOS. For adolescents who have features of PCOS but do not meet diagnostic criteria an 'at risk' label can be considered with appropriate symptomatic treatment and regular re-evaluations. Menstrual cycle re-evaluation can occur over 3 years post menarche and where only menstrual irregularity or hyperandrogenism are present initially, evaluation with ultrasound can occur after 8 years post menarche. Screening for anxiety and depression is required and assessment of eating disorders warrants consideration. Available data endorse the benefits of healthy lifestyle interventions to prevent excess weight gain and should be recommended. For symptom management, the combined oral contraceptive pill and/or metformin may be beneficial.

CONCLUSIONS

Extensive international engagement accompanied by rigorous processes honed both diagnostic criteria and treatment recommendations for PCOS during adolescence.

Polycystic Ovary Syndrome: Pathophysiology, Presentation, and Treatment With Emphasis on Adolescent Girls

Polycystic ovary syndrome (PCOS) is a heterogeneous disorder characterized by hyperandrogenism and chronic anovulation. Depending on diagnostic criteria, 6% to 20% of reproductive aged women are affected. Symptoms of PCOS arise during the early pubertal years. Both normal female pubertal development and PCOS are characterized by irregular menstrual cycles, anovulation, and acne. Owing to the complicated interwoven pathophysiology, discerning the inciting causes is challenging. Most available clinical data communicate findings and outcomes in adult women. Whereas the Rotterdam criteria are accepted for adult women, different diagnostic criteria for PCOS in adolescent girls have been delineated. Diagnostic features for adolescent girls are menstrual irregularity, clinical hyperandrogenism, and/or hyperandrogenemia. Pelvic ultrasound findings are not needed for the diagnosis of PCOS in adolescent girls. Even before definitive diagnosis of PCOS, adolescents with clinical signs of androgen excess and oligomenorrhea/amenorrhea, features of PCOS, can be regarded as being "at risk for PCOS." Management of both those at risk for PCOS and those with a confirmed PCOS diagnosis includes education, healthy lifestyle interventions, and therapeutic interventions targeting their symptoms. Interventions can include metformin, combined oral contraceptive pills, spironolactone, and local treatments for hirsutism and acne. In addition to ascertaining for associated comorbidities, management should also include regular follow-up visits and planned transition to adult care providers. Comprehensive knowledge regarding the pathogenesis of PCOS will enable earlier identification of girls with high propensity to develop PCOS. Timely implementation of individualized therapeutic interventions will improve overall management of PCOS during adolescence, prevent associated comorbidities, and improve quality of life.

An International Consortium Update: Pathophysiology, Diagnosis, and Treatment of Polycystic Ovarian Syndrome in Adolescence

This paper represents an international collaboration of paediatric endocrine and other societies (listed in the Appendix) under the International Consortium of Paediatric Endocrinology (ICPE) aiming to improve worldwide care of adolescent girls with polycystic ovary syndrome (PCOS)1. The manuscript examines pathophysiology and guidelines for the diagnosis and management of PCOS during adolescence. The complex pathophysiology of PCOS involves the interaction of genetic and epigenetic changes, primary ovarian abnormalities, neuroendocrine alterations, and endocrine and metabolic modifiers such as anti-Müllerian hormone, hyperinsulinemia, insulin resistance, adiposity, and adiponectin levels. Appropriate diagnosis of adolescent PCOS should include adequate and careful evaluation of symptoms, such as hirsutism, severe acne, and menstrual irregularities 2 years beyond menarche, and elevated androgen levels. Polycystic ovarian morphology on ultrasound without hyperandrogenism or menstrual irregularities should not be used to diagnose adolescent PCOS. Hyperinsulinemia, insulin resistance, and obesity may be present in adolescents with PCOS, but are not considered to be diagnostic criteria. Treatment of adolescent PCOS should include lifestyle intervention, local therapies, and medications. Insulin sensitizers like metformin and oral contraceptive pills provide short-term benefits on PCOS symptoms. There are limited data on anti-androgens and combined therapies showing additive/synergistic actions for adolescents. Reproductive aspects and transition should be taken into account when managing adolescents.

Metformin and pioglitazone combination therapy ameliorate polycystic ovary syndrome through AMPK/PI3K/JNK pathway

Polycystic ovary syndrome (PCOS) is a common gynecological endocrine disorder, which results in health problems such as menstrual disorders, hyperandrogenism and persistent anovulation. Hyperandrogenism and insulin resistance are the basic characteristics of PCOS. To investigate the combined effect of metformin and pioglitazone on POCS and the potential mechanisms, a rat model of PCOS was established by intramuscular injection of estradiol valerate (EV). The effect of metformin and pioglitazone monotherapy or combination therapy in control rats and PCOS rats was evaluated, involving the testosterone level, follicular development and insulin resistance. The potential mechanism for the therapeutic effect of metformin and pioglitazone on POCS was explored through using three inhibitors of the 5'adenosine monophosphate-activated protein kinase (AMPK)/phosphoinositide-3 kinase (PI3K)/c-Jun N-terminal kinase (JNK) pathway (Compound C, Wortmannin and SP600125). The results showed that EV-induced PCOS rats demonstrated hyperandrogenemia, hyperinsulinemia and follicular dysplasia. Metformin or pioglitazone monotherapy significantly suppressed the high level of testosterone, reduced the raised percentage of cystic follicles and primary follicles, promoted the number of early antral follicles, and markedly decreased the high concentration of fasting insulin and homeostatic model assessment for insulin resistance index in PCOS rats. In addition, metformin and pioglitazone combination therapy demonstrated greater efficacy than its individual components. Furthermore, individual or joint treatment with metformin and pioglitazone affected the phosphorylation level of JNK in PCOS rats. Compound C and Wortmannin eliminated the effect of metformin and pioglitazone combination therapy on improving the follicular growth in PCOS rats, whereas SP600125 treatment enhanced this combination therapy effect. These data suggested that metformin and pioglitazone combination therapy demonstrated great efficacy in ameliorating PCOS through regulating the AMPK/PI3K/JNK pathway.

Metformin or Oral Contraceptives for Adolescents With Polycystic Ovarian Syndrome: A Meta-analysis

BACKGROUND

Polycystic ovarian syndrome (PCOS) is a common disease. There is limited evidence to support various treatment choices. This leads to variable treatment practices.

OBJECTIVES

To conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the use of metformin versus oral contraceptive pills (OCPs) for the treatment of PCOS in adolescents aged 11 to 19 years.

DATA SOURCES

We performed literature searches through Ovid Medline, Ovid Embase, Cochrane Central Register of Controlled Trials, and gray literature resources, up to January 29, 2015.

STUDY SELECTION AND DATA EXTRACTION

Two reviewers screened titles and abstracts of identified citations, assessed full text eligibility, and extracted information from eligible trials.

RESULTS

Four RCTs met the inclusion and exclusion criteria. The reviewed evidence came from 170 patients. Overall, OCP treatment resulted in modest improvement in menstrual cycle frequency (weighted mean difference [WMD] = 0.27, P < .01, 95% confidence interval [CI] -0.33 to -0.21) and mild reduction of acne scores (WMD = 0.3, P = .02, 95% CI 0.05 to 0.55). While metformin resulted in greater BMI reduction (WMD = -4.02, P < .01, 95% CI -5.23 to -2.81) it was associated with decreased dysglycemia prevalence (risk ratio: 0.41, P = .02, 95% CI 0.19 to 0.86) and improved total cholesterol and low-density lipoprotein levels. Metformin and OCPs were similar in terms of impact on hirsutism.

CONCLUSIONS AND LIMITATIONS

Current evidence is derived from very low to low quality evidence. Therefore, treatment choice should be guided by patient values and preferences while balancing potential side effects. Future high quality RCTs are needed to address several questions for the treatment of adolescents with PCOS.