Metformin use during pregnancy: Current evidence and clinical considerations
DOI:
https://doi.org/10.14748/r6s8n597Keywords:
“metformin”, “pregnancy”, “diabetes”Abstract
Introduction:
Metformin exerts beneficial effects on glycaemic control by improving insulin sensitivity, which leads to inhibition of hepatic gluconeogenesis and glycogenolysis. Clinically, it is widely used in the management of type 2 diabetes mellitus and other insulin-resistant conditions. In recent years, its use during pregnancy has increased, particularly in improving maternal metabolic control.
Aim:
The aim of this article is to review and analyse current evidence on the efficacy, safety, and clinical applications of metformin use during pregnancy, focusing on maternal and neonatal outcomes, pharmacological considerations, and practical implications for clinical practice.
Materials and Methods:
A narrative review of the PubMed database was conducted using the following keywords: “metformin”, “pregnancy”, “gestational diabetes”, “type 2 diabetes”, “maternal outcomes”, “neonatal outcomes”, and “safety”. The initial search identified 175 articles. After screening titles and abstracts and application of the inclusion and exclusion criteria, 65 articles were included in the review.
Results:
In the context of pregnancy, metformin use has generated significant interest and debate. While traditional guidelines have favoured insulin for gestational diabetes mellitus (GDM), emerging evidence supports metformin as a viable alternative due to its efficacy, cost-effectiveness, and convenience. However, concerns persist regarding its transplacental passage, potential long-term effects on offspring, and variable efficacy across different patient profiles. Notably, randomised trials such as the Metformin in Gestational Diabetes (MiG), Metformin in Women with Type 2 Diabetes in Pregnancy (MiTY), and Metformin Plus Insulin for Preexisting Diabetes or Gestational Diabetes in Early Pregnancy (MOMPOD) studies and subsequent cohort follow-ups indicate that metformin can reduce maternal weight gain and neonatal complications without major safety concerns. Nonetheless, limitations include inconsistent glycaemic control in some patients and inconclusive data on long-term child development.
Conclusion:
Recent guidelines from the WHO, FDA, EMA, and NICE, along with the latest recommendations from leading diabetes associations and societies such as EASD, ADA, and ESE, reflect a cautiously evolving stance on metformin use during pregnancy, generally endorsing its use when insulin is unsuitable. While short-term safety appears acceptable, further longitudinal studies are needed to clarify its developmental impact on offspring. Overall, metformin remains a cornerstone in diabetes management with expanding potential, warranting nuanced consideration in pregnancy and beyond.
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