Which statement about risk factors for postpartum uterine atony is true?

• A. Overdistended uterus.
• B. Prolonged labor.
• C. High parity.
• D. All of the above.

Answer: (D)

Uterine atony is most likely when the uterus fails to contract firmly after delivery, so it can’t compress the blood vessels and stop bleeding. Each of these factors can weaken uterine tone. An overdistended uterus, such as from a large baby, twins, or too much amniotic fluid, stretches the myometrium and makes strong contraction less likely. Prolonged labor exhausts the uterine muscles, reducing their ability to generate effective contractions. High parity means the uterus has been stretched many times, which can diminish its contractile efficiency. Because all three scenarios raise the risk of poor uterine contraction, they collectively represent true risk factors for postpartum uterine atony.