Which of the following is a sign that may indicate a complication postpartum?

The sudden onset of a severe headache is a significant indicator of a possible postpartum complication, particularly when considering conditions such as eclampsia or postpartum preeclampsia. These conditions can occur after childbirth, characterized by high blood pressure and can lead to serious complications if left unaddressed. A severe headache that appears suddenly may suggest an accumulation of pressure or issues related to vascular health, necessitating immediate evaluation and management.

In contrast, light spotting is generally common in the postpartum period as the body begins to shed the uterine lining and there may be some residual blood from the delivery. Pain that gradually decreases is also considered normal as the body heals after childbirth, indicating a typical recovery process rather than a complication. Feeling tired is a common experience in the early postpartum period due to the physical and emotional demands of caring for a newborn, but it doesn't inherently signal a complication unless accompanied by other concerning symptoms. Thus, the sudden severe headache stands out as a clear warning sign of a potential serious issue requiring prompt medical attention.