A nurse is preparing to administer methylergonovine IM for a client who had a vaginal delivery earlier that day. The nurse should explain to the client that this medication will help prevent which of the following?

The correct answer is C: Postpartum hemorrhage. Methylergonovine is a uterotonic medication used to prevent or manage postpartum hemorrhage by promoting uterine contractions and reducing the risk of excessive bleeding. It helps the uterus to contract and close off blood vessels, which can prevent excessive bleeding after delivery.
Incorrect choices:
A: Postpartum infection - Methylergonovine does not prevent postpartum infection; it is specifically indicated for preventing hemorrhage.
B: Hypertension - Methylergonovine may cause hypertension as a side effect, but it is not its primary purpose.
D: Thromboembolic events - Methylergonovine does not prevent thromboembolic events; it works on the uterus to prevent hemorrhage.