What is a common reason for delayed involution or prolonged lochia?

• A. Uterine subinvolution due to retained products, infection, or poor uterine tone.
• B. Adequate rest.
• C. Normal postpartum changes only.
• D. Excessive bladder distension.

Answer: (A)

Delayed involution and prolonged lochia happen when the uterus doesn’t return to its prepregnant size as expected. The most common reason is uterine subinvolution, which occurs when the uterus can’t contract normally because placental tissue remains (retained products), infection such as endometritis inflames the uterus, or the uterine muscles have poor tone. Retained tissue keeps the uterus enlarged and lochia ongoing; infection disrupts normal uterine function and contraction; and weak uterine tone allows less effective contraction, so bleeding and discharge persist longer. Rest and normal postpartum healing help, so those don’t explain a delay. Excessive bladder distension can interfere with uterus positioning and contraction in some cases, but it’s not the primary cause of delayed involution.