ArticleBMJ (Clinical research ed.)2018
Metformin exposure in first trimester of pregnancy and risk of all or specific congenital anomalies: exploratory case-control study.
Article in BMJ (Clinical research ed.), 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 42 papers, 4 of them syntheses that pooled it.
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Who cites it
42 citing papers in PubMed, 4 syntheses or guidelines pooled it.
- Preexisting Diabetes and Pregnancy: An Endocrine Society and European Society of Endocrinology Joint Clinical Practice Guideline.The Journal of clinical endocrinology and metabolism · 2025Guideline
- Fetal and post-natal outcomes in offspring after intrauterine metformin exposure: A systematic review and meta-analysis of animal experiments.Diabetic medicine : a journal of the British Diabetic Association · 2024Pooled it
- Major malformations risk following early pregnancy exposure to metformin: a systematic review and meta-analysis.BMJ open diabetes research & care · 2023 · on this mapPooled it
- Maternal obesity and metabolic disorders associate with congenital heart defects in the offspring: A systematic review.PloS one · 2021Pooled it
- Cognitive function in metformin exposed children, born to mothers with PCOS - follow-up of an RCT.BMC pediatrics · 2020Trial
- Gabapentin and Pregabalin Use in First Trimester of Pregnancy and Risk of Specific Congenital Anomalies: An IMI ConcePTION European Case-Malformed Control Study.Drug safety · 2026Article
- The EUROmediCAT Network and Databases: A Resource for Pharmacovigilance in Pregnancy.Pharmacoepidemiology and drug safety · 2026Article
- RelA Inhibits Embryonic Myogenesis by Coordinately Regulating a Novel Distal Enhancer of Myogenin.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2025Article
- A narrative review of metformin in pregnancy: Navigating benefit and uncertainty.Diabetes, obesity & metabolism · 2025Review
- Imeglimin, unlike metformin, does not perturb differentiation of human induced pluripotent stem cells towards pancreatic β-like cells and rather enhances gain in β cell identity gene sets.Journal of diabetes investigation · 2025Article
- Metformin in gestational diabetes: physiological actions and clinical applications.Nature reviews. Endocrinology · 2025Review
- Investigating the Therapeutic Effects of Bushen Huoxue Formula Combined with Aerobic Exercise on Reproductive Function in Obese Polycystic Ovary Syndrome: An Experimental Study Based on the Integration of Sports and Medicine.International journal of general medicine · 2025Article
- Maternal periconception hyperglycemia, preconception diabetes, and risk of major congenital malformations in offspring.Human reproduction (Oxford, England) · 2024Article
- Single-cell RNA transcriptomics in mice reveals embryonic origin of fibrosis due to maternal obesity.EBioMedicine · 2024Article
- Efficacy and safety of metformin during pregnancy: an update.Endocrine · 2024Review
- Repurposing Metformin for the Treatment of Atrial Fibrillation: Current Insights.Vascular health and risk management · 2024Review
- International evidence-based guideline on assessment and management of PCOS-A Nordic perspective.Acta obstetricia et gynecologica Scandinavica · 2024Article
- Position paper of the Italian Association of Medical Diabetologists (AMD), Italian Society of Diabetology (SID), and the Italian Study Group of Diabetes in pregnancy: Metformin use in pregnancy.Acta diabetologica · 2023Review
- Metformin in Gestational Diabetes Mellitus: To Use or Not to Use, That Is the Question.Pharmaceuticals (Basel, Switzerland) · 2023Review
- Immunomodulatory Effects of Metformin Treatment in Pregnant Women With PCOS.The Journal of clinical endocrinology and metabolism · 2023 · on this mapArticle
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Authors and funding
14 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveTo investigate whether exposure to metformin during the first trimester of pregnancy, for diabetes or other indications, increases the risk of all or specific congenital anomalies.
designPopulation based exploratory case-control study using malformed controls. Cases of 29 specific subgroups of non-genetic anomalies, and all non-genetic anomalies combined, were compared with controls (all other non-genetic anomalies or genetic syndromes).
setting11 EUROmediCAT European congenital anomaly registries surveying 1 892 482 births in Europe between 2006 and 2013.
participants50 167 babies affected by congenital anomaly (41 242 non-genetic and 8925 genetic) including live births, fetal deaths from 20 weeks' gestation, and terminations of pregnancy for fetal anomaly.
main outcome measureOdds ratios adjusted for maternal age, registry, multiple birth, and maternal diabetes status.
results168 babies affected by congenital anomaly (141 non-genetic and 27 genetic) were exposed to metformin, 3.3 per 1000 births. No evidence was found for a higher proportion of exposure to metformin during the first trimester among babies with all non-genetic anomalies combined compared with genetic controls (adjusted odds ratio 0.84, 95% confidence interval 0.55 to 1.30). The only significant result was for pulmonary valve atresia (adjusted odds ratio 3.54, 1.05 to 12.00, compared with non-genetic controls; 2.86, 0.79 to 10.30, compared with genetic controls).
conclusionsNo evidence was found for an increased risk of all non-genetic congenital anomalies combined following exposure to metformin during the first trimester, and the one significant association was no more than would be expected by chance. Further surveillance is needed to increase sample size and follow up the cardiac signal, but these findings are reassuring given the increasing use of metformin in pregnancy.
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