Final answer:
Insulin requirements increase during the third trimester of pregnancy and decrease after delivery in the postpartum period.
Step-by-step explanation:
During pregnancy, insulin requirements increase during the third trimester and decrease after delivery in the postpartum period. This is because during pregnancy, the demand for glucose is higher due to the growth and development of the fetus. Insulin helps transport glucose into cells to meet this increased demand. After delivery, insulin requirements decrease as the body no longer needs to support fetal growth.