Final answer:
The nurse should respond that a decrease in sexual desire during the first trimester of pregnancy is normal, but it often returns during the second trimester.
Step-by-step explanation:
The nurse should respond with option A: "That sounds normal. In many cases, sexual desire decreases in the first trimester, but it increases again during the second trimester."
In the first trimester of pregnancy, many women experience hormonal changes that can affect their sexual desire. The increase in progesterone levels can lead to a decrease in libido. However, as the pregnancy progresses into the second trimester, hormone levels stabilize, and sexual desire often returns.
By addressing the patient's concern and providing reassurance, the nurse can support the patient during this normal phase of pregnancy.