Gestational diabetes is a pregnancy complication characterized by elevated blood glucose levels. It typically occurs when high blood glucose levels are first diagnosed during pregnancy and affects about 4% of all pregnancies. In most cases, blood glucose levels return to normal after the baby is born.
Glucose, a simple sugar formed through digestion and metabolism of food, serves as the main energy source for the body’s cells. Insulin, produced by the pancreas, is necessary for proper utilization of glucose by the cells. In diabetes, the pancreas either fails to produce enough insulin or the cells become resistant to its effects, leading to elevated blood glucose levels.
In gestational diabetes, hormonal changes during pregnancy, including increased insulin demand, contribute to insulin resistance. Although women with gestational diabetes produce sufficient insulin, its effectiveness is partially inhibited by hormones produced by the placenta, such as progesterone, prolactin, estrogen, cortisol, and human placental lactogen. Insulin resistance typically develops around 20 to 28 weeks of pregnancy when the placenta secretes more of these hormones. While most women initially produce additional insulin to compensate for insulin resistance, gestational diabetes occurs when the pancreas cannot produce enough insulin to counteract the effects of these hormones.