Which of the following can indicate infection postpartum?

The presence of foul-smelling lochia and fever is a significant indication of infection in the postpartum period. Lochia is the vaginal discharge that occurs after childbirth and can provide important clues about a woman's recovery. Normal lochia is typically odorless, and any foul odor can signal an infection, such as endometritis, which is an infection of the uterine lining. The addition of fever, which is often a systemic response to infection, further supports the likelihood of a postpartum infection.

In contrast, the other options do not align with the typical signs of infection. Rare bleeding and consistent energy may indicate a normal recovery, while a boggy uterus with little bleeding may suggest uterine atony rather than infection. Increased appetite and sleepiness also do not typically point towards an infection and could reflect normal postpartum exhaustion rather than systemic illness. Overall, the combination of foul-smelling lochia and fever is highly indicative of a potential infection that requires medical evaluation and intervention.