Insulin resistance is a state of reduced tissue response to the effect of insulin on blood sugar metabolism. Insulin resistance triggers higher insulin levels. Glucose can’t get into the cells, a usual function of insulin, so higher and higher levels of insulin are needed.
In general, normal pregnancy is associated with insulin resistance. However, insulin resistance is much worse in pregnant women with gestational diabetes, a condition that affects 10% of pregnancies. No one knows why pregnancy is associated with insulin resistance.
Gestational diabetes usually, but not always, disappears after the pregnancy is over. Since gestational diabetes affects up to 10% of pregnancies, some scientists think it may be a natural phenomenon.