The usage of insulin for pregnant women is not much different from that of the general population, with subcutaneous injection being the mainstay. If using short-acting insulin before meals, it is recommended to inject it for the outer 1/3 of the upper arm as the injection area. For the injection of medium-acting insulin and long-acting insulin, you can choose to inject insulin for the outer side of the thigh, which is more conducive to the absorption of insulin. Injections should be subcutaneous and not into the muscle. If the drug is injected into the muscle, it will be absorbed too quickly, which will easily lead to hypoglycemia. When injecting, try to rotate each part of the injection, if you always inject in one part, it is easy to form hard knots. In the second half of pregnancy, due to the increase of insulin resistance in the second half of pregnancy, the blood sugar of pregnant women will rise significantly, so the dose of insulin used in the second half of pregnancy will be adjusted, and it is recommended to monitor blood sugar regularly and make a plan under the guidance of physicians. Each person has a different constitution and different sensitivity to insulin, so each pregnant woman with diabetes should draw up a specific treatment plan and gradually increase the insulin dosage to prevent hypoglycemia. Severe hypoglycemia may lead to fetal danger, and it has been reported in the literature that the probability of fetal death and fetal abnormalities in pregnant women with hypoglycemia is four times higher than that of pregnant women with normal blood sugar. Insulin for pregnant women with diabetes generally does not affect fetal development, but it is important to note that there may be hypoglycemic reactions during the first 1-2 injections, so pay attention to preparing sugar cubes and take them as soon as possible once there is a hypoglycemic reaction, and you can start injecting slowly with small doses and gradually adjust the treatment.