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Reproductive Biology and Endocrinology

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Open Access 01-12-2021 | Metformin | Review

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

Authors: Lifang Yuan, Hongbo Wu, Weiyu Huang, Yin Bi, Aiping Qin, Yihua Yang

Published in: Reproductive Biology and Endocrinology | Issue 1/2021

Abstract

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.

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Title: The function of metformin in endometrial receptivity (ER) of patients with polycyclic ovary syndrome (PCOS): a systematic review and meta-analysis
Authors: Lifang Yuan
Hongbo Wu
Weiyu Huang
Yin Bi
Aiping Qin
Yihua Yang
Publication date: 01-12-2021
Publisher: BioMed Central
Keywords: Metformin
Miscarriage
Published in: Reproductive Biology and Endocrinology / Issue 1/2021
Electronic ISSN: 1477-7827
DOI: https://doi.org/10.1186/s12958-021-00772-7

At a glance: The STEP trials

Springer Medicine

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

Abstract

Background

Methods

Results

Conclusion

At a glance: The STEP trials

Springer Medicine

Abstract

Background

Methods

Results

Conclusion

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