Effect of metformin on adiponectin in PCOS: A meta-analysis and a systematic review.

BACKGROUND: Conflicting results have been reported regarding the effect of metformin on adiponectin levels in women with polycystic ovary syndrome (PCOS). This meta-analysis reviewed all studies comparing adiponectin levels before and after metformin treatment in PCOS women. Additionally, changes in other indicators, including long-term complications associated with PCOS, such as inflammatory, metabolism factors and hormonal profile, were investigated following metformin treatment. We conducted subgroup analysis based on body mass index (BMI) stratification and appropriate pooling. METHODS: We searched literature in PUBMED, EMBASE, the Cochrane Library, and CNKI databases. The main meta-analysis included 11 studies containing data on 353 subjects. RESULTS: Metformin treatment was associated with significantly increased serum adiponectin concentrations [10 studies, random-effects SMD (95% CI) -0.58 [-1.03, -0.13]; I2 = 86%; P = 0.01]. Additionally, the meta-analysis revealed that circulating tumor necrosis factor-α(TNF-α) and C-reactive protein (CRP) concentrations were significantly decreased after metformin treatment, with corresponding SMDs of 1.01 (95% CI: 0.74-1.28, P＜0.00001) and 0.48(95% CI: 0.35-0.60, P＜0.00001). CONCLUSION: Following metformin administration, serum adiponectin concentrations of PCOS women were found to be significantly increased, accompanied by a significant improvement in other indicators. Further investigation with a larger sample size should be conducted to validate optimal dose and duration of metformin.

Glucocorticoid supplementation improves reproductive outcomes in infertile women with antithyroid autoimmunity undergoing ART: A meta-analysis.

BACKGROUND: Thyroid autoimmune disease (TAI) has been verified to be related to multiple adverse pregnancy outcomes. A growing number of evidences highlight the protective roles of glucocorticoid on the treatments of TAI. This meta-analysis aimed to study whether it is beneficial to add glucocorticoid treatment in infertile women with TAI when they are undergoing assisted reproductive technology (ART). METHODS: We conducted a systematic search in PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), WanFang database, Weipu China Science and Technology Journal Databases (VIP database) up to September 10, 2020. The Revman 5.3 software was utilized for data statistics. We used a random-effects model to analyze data and the odds ratio (OR) combining with 95% confidence interval (95% CI) were employed to reveal the results. RESULTS: Three publications with 237 antithyroid antibody (ATA)-positive and 384 ATA-negative women were included in the final analysis. Overall, glucocorticoid therapy showed satisfying effects on improving clinical pregnancy rate (OR = 4.63, 95% CI [2.23, 9.58], I2 = 0.0%, P < .0001) and live birth rate (OR = 3.19, 95% CI [1.13, 9.04], I2 = 0.0%, P = .03) of ATA-positive women compared with control group. However, it seems that glucocorticoid showed no significant difference in the abortion rate (OR = 0.62, 95% CI [0.09, 4.32], I2 = 35%, P = .64) and oocyte recovery (OR = 2.26, 95% CI [-1.46, 5.99], I2 = 79%, P < .0001) between the 2 groups. CONCLUSIONS: Glucocorticoid may improve the pregnancy outcomes of ART women with ATA positive, but there is no significant reduction in the risk of miscarriage. Due to the limited enrolled references, glucocorticoid adjuvant therapy should be applied after more randomized controlled trials.