Metformin, a member of the biguanide class, is an anti-diabetic medication used to manage Type 2 diabetes, Gestational diabetes mellitus and Polycystic ovary syndrome. Prenatal exposure to increased Metformin levels can have lasting effects on mothers with diabetes, as chronic and persistent high blood glucose (hyperglycemia) is prevalent in diabetes mellitus.  Although metformin can cross biological barriers and influence cellular metabolic pathways, its effects on early embryonic development require further investigation. The present study evaluated the impact of different doses of metformin on embryonic growth and development using chick embryo (Gallus gallus domesticus). Chick embryos serve as a classic model for studying different stages of development and can be utilized in regenerative therapy. The fertilized eggs were categorized into two primary groups; group A served as the control group (normal saline), while group B represented the experimental group (metformin). The experimental group was further divided into three subgroups, each receiving different concentrations of metformin injections. Eggs from both group A and group B were injected at the 24-hour mark of incubation and examined on day 5 and 10 of incubation. Administering Metformin led to initial growth delays in chick embryos, along with alterations in their morphology. Metformin exposure was associated with alterations in embryonic morphology and extraembryonic vascular development compared with the control group. Treated embryos exhibited reduced peripheral vascular branching, vessel thinning, disruption of vascular organization, and reduced vascular density, with more pronounced alterations. These findings demonstrate that exposure to metformin during early chick embryonic development is associated with developmental and vascular alterations. The chick embryo model may therefore be useful for investigating the dose-dependent effects and underlying mechanisms of metformin-associated developmental toxicity. Further, molecular and mechanistic studies are required to clarify the pathways responsible for these developmental alterations.