Table 1. Advantages versus disadvantages of metformin versus insulin.

	Metformin	Insulin
Advantages	Convenience of an oral pill Lower cost/less resources No participant hypoglycaemia Less weight gain Improved adherence	Historically, first-line agent Highly effective Does not cross the placenta Confirmed fetal safety
Disadvantages	Crosses the placenta Possible low birth weight Possible risk of child obesity Gastrointestinal distress Risk of supplemental insulin	Injections/inconvenient Higher cost/high resources Participant hypoglycaemia Impractical for short-term use