The correct answer is choice B. Second trimester.

Gestational diabetes is high blood sugar that develops during pregnancy and usually disappears after giving birth. It can happen at any stage of pregnancy, but is more common in the second or third trimester. This is because hormonal changes that occur during pregnancy can affect the body’s ability to produce enough insulin, a hormone that helps control blood sugar levels.

Choice A is wrong because gestational diabetes is less likely to develop during the first trimester, when the hormonal changes are not as significant.

Choice C is wrong because gestational diabetes is usually diagnosed and treated before the third trimester, to prevent complications for the mother and the baby.

Choice D is wrong because gestational diabetes is not a postpartum condition, although some women may have a higher risk of developing type 2 diabetes later in life if they had gestational diabetes.

Normal ranges for blood sugar levels during pregnancy are:

• Before meals: 60 to 95 mg/dL

• One hour after meals: 100 to 129 mg/dL

• Two hours after meals: 70 to 119 mg/dL