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Nutrients Aug 2020Zinc is an essential microelement that plays many important functions in the body. It is crucial for the regulation of cell growth, hormone release, immunological...
Zinc is an essential microelement that plays many important functions in the body. It is crucial for the regulation of cell growth, hormone release, immunological response and reproduction. This review focuses on its importance in the reproductive system of women of reproductive and postmenopausal ages, not including its well described role in pregnancy. Only recently, attention has been drawn to the potential role of zinc in polycystic ovary syndrome (PCOS), dysmenorrhea, or endometriosis. This review is mainly based on 36 randomized, controlled studies on reproductive, pre- and post-menopausal populations of women and on research trying to explain the potential impact of zinc and its supplementation in the etiology of selected female reproductive system disorders. In women with PCOS, zinc supplementation has a positive effect on many parameters, especially those related to insulin resistance and lipid balance. In primary dysmenorrhea, zinc supplementation before and during each menstrual cycle seems to be an important factor reducing the intensity of menstrual pain. On the other hand, little is known of the role of zinc in endometriosis and in postmenopausal women. Therefore, further studies explaining the potential impact of zinc and its supplementation on female reproductive system would be highly advisable and valuable.
Topics: Adult; Dietary Supplements; Dysmenorrhea; Endometriosis; Female; Humans; Insulin Resistance; Lipid Metabolism; Male; Menstrual Cycle; Polycystic Ovary Syndrome; Pregnancy; Reproduction; Zinc
PubMed: 32824334
DOI: 10.3390/nu12082464 -
BMC Medicine Aug 2023The results of human observational studies on the correlation between gut microbiota perturbations and polycystic ovary syndrome (PCOS) have been contradictory. This... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The results of human observational studies on the correlation between gut microbiota perturbations and polycystic ovary syndrome (PCOS) have been contradictory. This study aimed to perform the first systematic review and meta-analysis to evaluate the specificity of the gut microbiota in PCOS patients compared to healthy women.
METHODS
Literature through May 22, 2023, was searched on PubMed, Web of Science, Medline, Embase, Cochrane Library, and Wiley Online Library databases. Unreported data in diversity indices were filled by downloading and processing raw sequencing data. Systematic review inclusion: original studies were eligible if they applied an observational case-control design, performed gut microbiota analysis and reported diversity or abundance measures, sampled general pre-menopausal women with PCOS, and are longitudinal studies with baseline comparison between PCOS patients and healthy females. Systematic review exclusion: studies that conducted interventional or longitudinal comparisons in the absence of a control group. Two researchers made abstract, full-text, and data extraction decisions, independently. The Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodologic quality. Hedge's g standardized mean difference (SMD), confidence intervals (CIs), and heterogeneity (I) for alpha diversity were calculated. Qualitative syntheses of beta-diversity and microbe alterations were performed.
RESULTS
Twenty-eight studies (n = 1022 patients, n = 928 control) that investigated gut microbiota by collecting stool samples were included, with 26 and 27 studies having provided alpha-diversity and beta-diversity results respectively. A significant decrease in microbial evenness and phylogenetic diversity was observed in PCOS patients when compared with control participants (Shannon index: SMD = - 0.27; 95% CI, - 0.37 to - 0.16; phylogenetic diversity: SMD = - 0.39; 95% CI, -- 0.74 to - 0.03). We also found that reported beta-diversity was inconsistent between studies. Despite heterogeneity in bacterial relative abundance, we observed depletion of Lachnospira and Prevotella and enrichment of Bacteroides, Parabacteroides, Lactobacillus, Fusobacterium, and Escherichia/Shigella in PCOS. Gut dysbiosis in PCOS, which might be characterized by the reduction of short-chain fatty acid (SCFA)-producing and bile-acid-metabolizing bacteria, suggests a shift in balance to favor pro-inflammatory rather than anti-inflammatory bacteria.
CONCLUSIONS
Gut dysbiosis in PCOS is associated with decreased diversity and alterations in bacteria involved in microbiota-host crosstalk.
TRIAL REGISTRATION
PROSPERO registration: CRD42021285206, May 22, 2023.
Topics: Humans; Female; Gastrointestinal Microbiome; Polycystic Ovary Syndrome; Dysbiosis; Phylogeny; Microbiota
PubMed: 37559119
DOI: 10.1186/s12916-023-02975-8 -
Reproductive Biomedicine Online Aug 2019This meta-analysis aimed to evaluate the efficacy and safety of glucagon-like peptide 1 (GLP-1) receptor agonists for women with polycystic ovary syndrome (PCOS) by... (Comparative Study)
Comparative Study Meta-Analysis
This meta-analysis aimed to evaluate the efficacy and safety of glucagon-like peptide 1 (GLP-1) receptor agonists for women with polycystic ovary syndrome (PCOS) by comparing their effect with that of metformin. Electronic databases (PubMed, EMBASE, Cochrane Library, WanFang Database, CNKI) dating from their establishment to June 2018 were searched to find all randomized controlled trials (RCTs) reporting the efficacy of GLP-1 receptor agonists versus metformin for patients with PCOS. Therapeutic variables included menstrual cycle, sex hormone and clinical manifestations, glucose metabolism and other metabolic indexes. Eight RCTs among 462 related articles were included in the meta-analysis. Compared with metformin, GLP-1 receptor agonists were more effective in improving insulin sensitivity (standard mean difference [SMD] -0.40, 95% confidence interval [CI] -0.74 to -0.06, P = 0.02) and reducing body mass index (SMD -1.02, 95% CI -1.85 to -0.19, P = 0.02) and abdominal girth (SMD -0.45, 95% CI -0.89 to -0.00, P = 0.05). GLP-1 receptor agonists were associated with a higher incidence of nausea and headache than metformin, but there were no significant differences in other data. Therefore, compared with metformin, GLP-1 receptor agonists might be a good choice for obese patients with PCOS, especially those with insulin resistance. The available evidence is, however, inconclusive given its moderate to low quality. More high-quality research is needed to assess the efficacy of a GLP-1 receptor agonist on women with PCOS.
Topics: Adult; Androgens; Blood Glucose; Female; Glucagon-Like Peptide-1 Receptor; Homeostasis; Humans; Metformin; Obesity; Polycystic Ovary Syndrome; Randomized Controlled Trials as Topic; Reproducibility of Results; Sample Size; Testosterone; Treatment Outcome; Young Adult
PubMed: 31229399
DOI: 10.1016/j.rbmo.2019.04.017 -
Human Reproduction (Oxford, England) Jun 2023What is the influence of body composition during childhood, adolescence, and adulthood, as well as metabolic parameters, on incident polycystic ovary syndrome (PCOS)? (Meta-Analysis)
Meta-Analysis
STUDY QUESTION
What is the influence of body composition during childhood, adolescence, and adulthood, as well as metabolic parameters, on incident polycystic ovary syndrome (PCOS)?
SUMMARY ANSWER
Excess body fat, even during childhood/adolescence, and metabolic parameters, suggestive of hyperinsulinaemia/insulin resistance, significantly impact the risk of PCOS in a linear fashion.
WHAT IS KNOWN ALREADY
Observational and Mendelian randomization (MR) data have demonstrated an association between adulthood overweight/obesity and development of PCOS. However, the contribution of body composition in childhood/adolescence to incident PCOS is unclear, as is the influence of childhood overweight/obesity.
STUDY DESIGN, SIZE, DURATION
We conducted a systematic review and meta-analysis and integrated our results with a previously published systematic review. Two blinded investigators screened abstracts published between November 2010 and May 2021. Furthermore, we incorporated summary statistics from genome-wide association study (GWAS) data in subjects of European ancestry. Adult overweight was defined as BMI ≥ 25 kg/m2 and obesity as BMI ≥ 30 kg/m2; in Asian subjects, overweight was defined as BMI ≥ 23 kg/m2 and obesity as BMI ≥ 25 kg/m2.
PARTICIPANTS/MATERIALS, SETTING, METHODS
We utilized meta-analysis and MR together to allow synthesis of genetic and observational data. For the systematic review, the search revealed 71 studies, of which 63 were included in meta-analysis by calculating odds ratios (ORs) using the random-effects model. Furthermore, we conducted a two-sample MR study of GWAS data to determine the impact of childhood and adult body size (defined categorically by BMI and childhood body size proportions), abnormal body composition and metabolic parameters (higher fasting serum insulin or lower sex hormone-binding globulin (SHBG) concentration) on the odds of incident PCOS via the inverse-variance weighted method.
MAIN RESULTS AND THE ROLE OF CHANCE
Significant associations were shown between body composition and PCOS incidence. From the systematic review/meta-analysis, women with overweight (OR 3.80, 2.87-5.03), obesity (OR 4.99, 3.74-6.67), and central obesity (OR 2.93, 2.08-4.12) had increased odds of PCOS. For adolescents with overweight and/or obesity, the PCOS odds were greater than for adults. From MR, for every standard deviation increase in BMI (4.8 kg/m2), the odds of PCOS increased by 2.76 (2.27-3.35). Childhood body size had an independent effect on PCOS odds after adjusting for adult body size (OR: 2.56, 1.57-4.20). Genetically determined body fat percentage (OR 3.05, 2.24-4.15), whole body fat mass (OR 2.53, 2.04-3.14), fasting serum insulin (OR 6.98, 2.02-24.13), and SHBG concentration (OR 0.74, 0.64-0.87) were all significantly associated with PCOS in a linear relation.
LIMITATIONS, REASONS FOR CAUTION
The meta-analysis included studies which were cross-sectional and retrospective, limiting our ability to determine causality. MR was limited by interrogating subjects only of European ancestry and including cases classified by either self-diagnosis or diagnostic criteria.
WIDER IMPLICATIONS OF THE FINDINGS
Our study demonstrates for the first time a critical role of the impact of excess childhood/adolescent adiposity on the pathophysiology of adult PCOS. Our results, driven by genetically determined childhood/adolescent body composition, higher BMI, hyperinsulinaemia, and lower SHBG, clearly favour obesity driving the metabolic, but not reproductive, PCOS phenotype. Overall, effective weight maintenance, even from the early years, is likely to reduce the risk of this reproductive endocrine disorder.
STUDY FUNDING/COMPETING INTEREST(S)
S.S.Z. was funded by a National Institute for Health and Care Research (NIHR) Academic Clinical Lectureship. U.A. is chair of the NIHR Steering Committee Trial-CASSANDRA-DN. No other authors declare any sources of funding or relevant conflicts of interest. The authors declare that the research was conducted in the absence of any commercial or financial relations that could be construed as a potential conflict of interest.
TRIAL REGISTRATION NUMBER
N/A.
Topics: Humans; Female; Polycystic Ovary Syndrome; Overweight; Adiposity; Retrospective Studies; Genome-Wide Association Study; Mendelian Randomization Analysis; Body Mass Index; Obesity; Insulin Resistance; Insulins
PubMed: 37015099
DOI: 10.1093/humrep/dead053 -
Medicine Apr 2020Polycystic ovary syndrome (PCOS) affects reproductive-aged women and is associated with increased prevalence of serious clinical problems including: reproductive... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Polycystic ovary syndrome (PCOS) affects reproductive-aged women and is associated with increased prevalence of serious clinical problems including: reproductive implications, metabolic dysfunction, and cardiovascular risk. Physical activity offers several health benefits for women with PCOS. The aim of this systematic review was to synthesize evidence on the effect of different types of exercise on reproductive function and body composition for women with PCOS.
METHODS
This was a systematic review and meta-analysis of randomized controlled trials (RCTs) following recommended review methods. We searched 6 databases: Cumulative Index of Nursing and Allied Health Literature; Embase; MEDLINE (via Ovid); PubMed; Sport Discus; and Web of Science; and we developed search strategies using a combination of Medical Subject Headings terms and text words related to exercise interventions for women with PCOS. There was no restriction on language or publication year. The search was conducted on April 16, 2019 and updated on November 15, 2019. Two authors independently screened citations, determined risk of bias and quality of evidence with Grading of Recommendations Assessment, Development and Evaluation. We conducted meta-analyses following recommended guidelines, and report results using standardized mean difference (SMD).
RESULTS
Ten RCTs (n = 533) were included in this review. Studies tested the following interventions: aerobic, resistance, and combined (aerobic/resistance) training programs. Most studies were small (average 32, range 15-124 participants), and of relatively short duration (8-32 weeks). There was high heterogeneity for outcomes of reproductive function (menstrual cycle, ovulation, and fertility). We noted low certainty evidence for little to no effect of exercise on reproductive hormones and moderate certainty evidence that aerobic exercise reduced body mass index (BMI) in women with PCOS: BMI SMD -0.35, 95% confidence interval -0.56 to -0.14, P = .001.
CONCLUSION
For women with PCOS, evidence is limited to discern the effect of exercise on major health outcomes (e.g., reproductive function). There is moderate certainty evidence that aerobic exercise alone is beneficial for reducing BMI in women with PCOS. Future studies should be conducted with longer duration, larger sample sizes, and should provide detailed information on menstrual cycle and fertility outcomes.PROSPERO Systematic review registration: 2017 CRD42017058869.
Topics: Exercise Therapy; Female; Humans; Polycystic Ovary Syndrome; Randomized Controlled Trials as Topic
PubMed: 32311937
DOI: 10.1097/MD.0000000000019644 -
Scientific Reports Mar 2022Gonadotropin-releasing hormone (GnRH) analogues are commonly used in clinical practice to prevent premature luteinizing hormone (LH) surge during In-Vitro Fertilization/... (Meta-Analysis)
Meta-Analysis
Gonadotropin-releasing hormone (GnRH) analogues are commonly used in clinical practice to prevent premature luteinizing hormone (LH) surge during In-Vitro Fertilization/ Intra-Cytoplasmic Sperm Injection (IVF/ICSI) cycles. This review aimed to summarize the available evidence comparing the effects of conventional GnRH antagonist protocols, the most commonly used GnRH antagonist protocols, and GnRH agonist protocols on IVF/ICSI outcomes in women with polycystic ovary syndrome (PCOS). A comprehensive electronic search was carried out in Pubmed, Cochrane CENTRAL, Scopus, Web of Science, CINAHL, TRIP, ClinicalTrials.gov and ISRCTN registry from inception until 24 November 2020 without any language or date restrictions. In addition, reference lists of eligible studies and previous meta-analyses were hand-searched to identify relevant studies. Eligible randomized controlled trials were those designed to compare the effects of conventional GnRH antagonist protocols and GnRH agonist protocols on IVF/ICSI outcomes in PCOS subjects. The Cochrane ROB 2.0 tool was used to assess the risk of bias of each study, and the GRADE assessment was used to evaluate the overall quality of evidence. Data synthesis and analyses were done using Review Manager 5.3 with the assistance of Revman Web. A random-effects model was used for all meta-analysis. Dichotomous outcomes were reported as Relative Risk (RR) and continuous outcomes as Weighted Mean Difference (WMD), both with 95% CIs. The primary outcomes were Live birth rate, Ongoing pregnancy rate, and Ovarian hyperstimulation syndrome (OHSS) rate. Other IVF outcomes were considered secondary outcomes. We included ten studies with 1214 randomized PCOS women. Using GnRH antagonist protocols led to a significantly lower OHSS rate (RR = 0.58; 95% CI: [0.44 to 0.77], P = 0.0002), shorter stimulation duration (WMD = - 0.91; 95% CI: [-1.45 to - 0.37] day, P = 0.0009), lower gonadotropin consumption (WMD = - 221.36; 95% CI: [- 332.28 to - 110.45] IU, P < 0.0001), lower E2 levels on hCG day (WMD = - 259.21; 95% CI: [- 485.81 to - 32.60] pg/ml, P = 0.02), thinner endometrial thickness on hCG day (WMD = - 0.73; 95% CI: [- 1.17 to - 0.29] mm, P = 0.001), and lower number of retrieved oocytes (WMD = - 1.82; 95% CI: [- 3.48 to - 0.15] oocytes, P = 0.03). However, no significant differences in live birth rate, ongoing pregnancy rate, clinical pregnancy rate, multiple pregnancy rate, miscarriage rate and cycle cancellation rate were seen between the GnRH antagonist protocols and the long GnRH agonist one. Although more cycles were cancelled due to poor ovarian response in the GnRH antagonist protocol (RR = 4.63; 95% CI: [1.49 to 14.41], P = 0.008), similar rates of cancellation due to risk of OHSS were noticed in both groups. The differences in IVF/ICSI outcomes may arise from the different patterns of gonadotropins suppression that the GnRH analogues exhibit during the early follicular phase of IVF/ICSI cycles and the divergent direct impacts of these analogues on ovaries and endometrial receptivity. The main evidence limitation was Imprecision. Conventional GnRH antagonist protocols represent a safer and more cost-effective treatment choice for PCOS women undergoing IVF/ICSI cycles than the standard long GnRH agonist protocol without compromising the IVF/ICSI clinical outcomes. The study had no sources of financial support and was prospectively registered at PROSPERO (International Prospective Register of Systematic Reviews) under registration number (CRD42021242476).
Topics: Clinical Protocols; Female; Fertilization in Vitro; Gonadotropin-Releasing Hormone; Gonadotropins; Hormone Antagonists; Humans; Ovarian Hyperstimulation Syndrome; Ovulation Induction; Polycystic Ovary Syndrome; Pregnancy; Pregnancy Rate; Sperm Injections, Intracytoplasmic
PubMed: 35292717
DOI: 10.1038/s41598-022-08400-z -
Human Reproduction Update Sep 2017Most reviews of IVF ovarian stimulation protocols have insufficiently accounted for various patient populations, such as ovulatory women, women with polycystic ovary...
BACKGROUND
Most reviews of IVF ovarian stimulation protocols have insufficiently accounted for various patient populations, such as ovulatory women, women with polycystic ovary syndrome (PCOS) or women with poor ovarian response, and have included studies in which the agonist or antagonist was not the only variable between the compared study arms.
OBJECTIVE AND RATIONALE
The aim of the current study was to compare GnRH antagonist protocols versus standard long agonist protocols in couples undergoing IVF or ICSI, while accounting for various patient populations and treatment schedules.
SEARCH METHODS
The Cochrane Menstrual Disorders and Subfertility Review Group specialized register of controlled trials and Pubmed and Embase databases were searched from inception until June 2016. Eligible trials were those that compared GnRH antagonist protocols and standard long GnRH agonist protocols in couples undergoing IVF or ICSI. The primary outcome was ongoing pregnancy rate. Secondary outcomes were: live birth rate, clinical pregnancy rate, number of oocytes retrieved and safety with regard to ovarian hyperstimulation syndrome (OHSS). Separate comparisons were performed for the general IVF population, women with PCOS and women with poor ovarian response. Pre-planned subgroup analyses were performed for various antagonist treatment schedules.
OUTCOMES
We included 50 studies. Of these, 34 studies reported on general IVF patients, 10 studies reported on PCOS patients and 6 studies reported on poor responders. In general IVF patients, ongoing pregnancy rate was significantly lower in the antagonist group compared with the agonist group (RR 0.89, 95% CI 0.82-0.96). In women with PCOS and in women with poor ovarian response, there was no evidence of a difference in ongoing pregnancy between the antagonist and agonist groups (RR 0.97, 95% CI 0.84-1.11 and RR 0.87, 95% CI 0.65-1.17, respectively). Subgroup analyses for various antagonist treatment schedules compared to the long protocol GnRH agonist showed a significantly lower ongoing pregnancy rate when the oral hormonal programming pill (OHP) pretreatment was combined with a flexible protocol (RR 0.74, 95% CI 0.59-0.91) while without OHP, the RR was 0.84, 95% CI 0.71-1.0. Subgroup analysis for the fixed antagonist schedule demonstrated no evidence of a significant difference with or without OHP (RR 0.94, 95% CI 0.79-1.12 and RR 0.94, 95% CI 0.83-1.05, respectively). Antagonists resulted in significantly lower OHSS rates both in the general IVF patients and in women with PCOS (RR 0.63, 95% CI 0.50-0.81 and RR 0.53, 95% CI 0.30-0.95, respectively). No data on OHSS was available from trials in poor responders.
WIDER IMPLICATIONS
In a general IVF population, GnRH antagonists are associated with lower ongoing pregnancy rates when compared to long protocol agonists, but also with lower OHSS rates. Within this population, antagonist treatment prevents one case of OHSS in 40 patients but results in one less ongoing pregnancy out of every 28 women treated. Thus standard use of the long GnRH agonist treatment is perhaps still the approach of choice for prevention of premature luteinization. In couples with PCOS and poor responders, GnRH antagonists do not seem to compromise ongoing pregnancy rates and are associated with less OHSS and therefore could be considered as standard treatment.
Topics: Female; Fertilization in Vitro; Gonadotropin-Releasing Hormone; Gonadotropins; Humans; Ovarian Hyperstimulation Syndrome; Ovulation Induction; Polycystic Ovary Syndrome; Pregnancy; Pregnancy Rate
PubMed: 28903472
DOI: 10.1093/humupd/dmx017 -
The Journal of Clinical Endocrinology... Jan 2024Polycystic ovary syndrome (PCOS) affects more than 1 in 10 women. (Meta-Analysis)
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).
Topics: Female; Humans; Metformin; Polycystic Ovary Syndrome; Contraceptives, Oral, Combined; Hypoglycemic Agents; Testosterone; Insulins
PubMed: 37554096
DOI: 10.1210/clinem/dgad465 -
Journal of Assisted Reproduction and... Oct 2020Increased oxidative stress has been identified as a pathogenetic mechanism in female infertility. However, the effect of specific antioxidants, such as coenzyme Q (CoQ),... (Meta-Analysis)
Meta-Analysis
Does coenzyme Q supplementation improve fertility outcomes in women undergoing assisted reproductive technology procedures? A systematic review and meta-analysis of randomized-controlled trials.
OBJECTIVE
Increased oxidative stress has been identified as a pathogenetic mechanism in female infertility. However, the effect of specific antioxidants, such as coenzyme Q (CoQ), on the outcomes after assisted reproductive technologies (ART) has not been clarified. The aim of this study was to systematically review and meta-analyze the best available evidence regarding the effect of CoQ supplementation on clinical pregnancy (CPR), live birth (LBR), and miscarriage rates (MR) compared with placebo or no-treatment in women with infertility undergoing ART.
METHODS
A comprehensive literature search was conducted in PubMed (MEDLINE), Cochrane, and Scopus, from inception to March 2020. Data were expressed as odds ratio (OR) with 95% confidence intervals (CI). The I index was employed for heterogeneity.
RESULTS
Five randomized-controlled trials fulfilled eligibility criteria (449 infertile women; 215 in CoQ group and 234 in placebo/no treatment group). Oral supplementation of CoQ resulted in an increase of CPR when compared with placebo or no-treatment (28.8% vs. 14.1%, respectively; OR 2.44, 95% CI 1.30-4.59, p = 0.006; I 32%). This effect remained significant when women with poor ovarian response and polycystic ovarian syndrome were analyzed separately. No difference between groups was observed regarding LBR (OR 1.67, 95% CI 0.66-4.25, p = 0.28; I 34%) and MR (OR 0.61, 95% CI 0.13-2.81, p = 0.52; I 0%).
CONCLUSIONS
Oral supplementation of CoQ may increase CPR when compared with placebo or no-treatment, in women with infertility undergoing ART procedures, without an effect on LBR or MR.
Topics: Female; Humans; Pregnancy; Antioxidants; Dietary Supplements; Fertility; Infertility, Female; Oxidative Stress; Polycystic Ovary Syndrome; Ubiquinone; Randomized Controlled Trials as Topic
PubMed: 32767206
DOI: 10.1007/s10815-020-01906-3 -
The Cochrane Database of Systematic... Nov 2017Polycystic ovary syndrome (PCOS) is characterised by infrequent or absent ovulation, and high levels of androgens and insulin (hyperinsulinaemia). Hyperinsulinaemia... (Meta-Analysis)
Meta-Analysis Review
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 increased risk of cardiovascular disease and diabetes mellitus. Insulin-sensitising agents such as metformin may be effective in treating PCOS-related anovulation.
OBJECTIVES
To evaluate the effectiveness and safety of insulin-sensitising drugs in improving reproductive and metabolic outcomes for women with PCOS undergoing ovulation induction.
SEARCH METHODS
We searched the following databases from inception to January 2017: 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 insulin-sensitising drugs compared with placebo, no treatment, or an ovulation-induction agent for women with oligo and anovulatory PCOS.
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, menstrual frequency and metabolic effects. We combined data to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs). We assessed statistical heterogeneity using the I statistic and reported quality of the evidence for primary outcomes using GRADE methodology.
MAIN RESULTS
We assessed the interventions metformin, clomiphene citrate, metformin plus clomiphene citrate, D-chiro-inositol, rosiglitazone and pioglitazone. We compared these with each other, placebo or no treatment. We included 48 studies (4451 women), 42 of which investigated metformin (4024 women). Evidence quality ranged from very low to moderate. Limitations were risk of bias (poor reporting of methodology and incomplete outcome data), imprecision and inconsistency. Metformin versus placebo or no treatmentThe evidence suggests that metformin may improve live birth rates compared with placebo (OR 1.59, 95% CI 1.00 to 2.51, 4 studies, 435 women, I = 0%, low-quality evidence). The metformin group experienced more gastrointestinal side effects (OR 4.76, 95% CI 3.06 to 7.41, 7 studies, 670 women, I = 61%, moderate-quality evidence) but had higher rates of clinical pregnancy (OR 1.93, 95% CI 1.42 to 2.64, 9 studies, 1027 women, I = 43%, moderate-quality evidence), ovulation (OR 2.55, 95% CI 1.81 to 3.59, 14 studies, 701 women, I = 58%, moderate-quality evidence) and menstrual frequency (OR 1.72, 95% CI 1.14 to 2.61, 7 studies, 427 women, I = 54%, low-quality evidence). There was no clear evidence of a difference in miscarriage rates (OR 1.08, 95% CI 0.50 to 2.35, 4 studies, 748 women, I = 0%, low-quality evidence). Metformin plus clomiphene citrate versus clomiphene citrate alone There was no conclusive evidence of a difference between the groups in live birth rates (OR 1.21, 95% CI 0.92 to 1.59, 9 studies, 1079 women, I = 20%, low-quality evidence), but gastrointestinal side effects were more common with combined therapy (OR 3.97, 95% CI 2.59 to 6.08, 3 studies, 591 women, I = 47%, moderate-quality evidence). However, the combined therapy group had higher rates of clinical pregnancy (OR 1.59, 95% CI 1.27 to 1.99, 16 studies, 1529 women, I = 33%, moderate-quality evidence) and ovulation (OR 1.57, 95% CI 1.28 to 1.92, 21 studies, 1624 women, I = 64%, moderate-quality evidence). There was a statistically significant difference in miscarriage rate per woman, with higher rates in the combined therapy group (OR 1.59, 95% CI 1.03 to 2.46, 9 studies, 1096 women, I = 0%, low-quality evidence) but this is of uncertain clinical significance due to low-quality evidence, and no clear difference between groups when we analysed miscarriage per pregnancy (OR 1.30, 95% CI 0.80 to 2.12, 8 studies; 400 pregnancies, I = 0%, low-quality evidence). Metformin versus clomiphene citrateWhen all studies were combined, findings for live birth were inconclusive and inconsistent (OR 0.71, 95% CI 0.49 to 1.01, 5 studies, 741 women, I = 86%, 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, I = 0%, very low-quality evidence), while data from the non-obese group showed a possible benefit from metformin, with high heterogeneity (OR 1.71, 95% CI 1.00 to 2.94, 3 studies, 241 women, I = 78%, very low-quality evidence). Similarly, among obese women taking metformin there were lower rates of clinical pregnancy (OR 0.34, 95% CI 0.21 to 0.55, 2 studies, 500 women, I = 0%, very low-quality evidence) and ovulation (OR 0.29, 95% CI 0.20 to 0.43 2 studies, 500 women, I = 0%, low-quality evidence) while among non-obese women, the metformin group had more pregnancies (OR 1.56, 95% CI 1.05 to 2.33, 5 studies, 490 women, I = 41%, very low-quality evidence) and no clear difference in ovulation rates (OR 0.81, 95% CI 0.51 to 1.28, 4 studies, 312 women, low-quality evidence, I=0%). There was no clear evidence of a difference in miscarriage rates (overall: OR 0.92, 95% CI 0.50 to 1.67, 5 studies, 741 women, I = 52%, very low-quality evidence). D-chiro-inositol (2 studies), rosiglitazone (1 study) or pioglitazone (1 study) versus placebo or no treatmentWe were unable to draw conclusions regarding other insulin-sensitising drugs as no studies reported primary outcomes.
AUTHORS' CONCLUSIONS
Our updated review suggests that metformin alone may be beneficial over placebo for live birth, although the evidence quality was low. When metformin was compared with clomiphene citrate, data for live birth were inconclusive, and our findings were limited by lack of evidence. Results differed by body mass index (BMI), emphasising the importance of stratifying results by BMI. An improvement in clinical pregnancy and ovulation suggests that clomiphene citrate remains preferable to metformin for ovulation induction in obese women with PCOS.An improved clinical pregnancy and ovulation rate with metformin and clomiphene citrate versus clomiphene citrate alone suggests that combined therapy may be useful although we do not know whether this translates into increased live births. Women taking metformin alone or with combined therapy should be advised that there is no evidence of increased miscarriages, but gastrointestinal side effects are more likely.
Topics: Abortion, Spontaneous; Anovulation; Clomiphene; Female; Humans; Hypoglycemic Agents; Infertility, Female; Inositol; Insulin Resistance; Live Birth; Metformin; Ovulation Induction; Pioglitazone; Polycystic Ovary Syndrome; Pregnancy; Pregnancy Rate; Randomized Controlled Trials as Topic; Rosiglitazone; Thiazolidinediones
PubMed: 29183107
DOI: 10.1002/14651858.CD003053.pub6