Which fetal monitoring finding is associated with abruptio placentae?

• A. Normal fetal heart rate
• B. Increased uterine resting tone
• C. Decreased contractions
• D. No changes

Answer: (B)

Abrupt placental separation irritates the uterus, causing it to become hypertonic and tense even between contractions. This increased resting tone is a hallmark finding because the uterus is trying to respond to the bleed and placental detachment, which reduces placental blood flow and risks fetal hypoxia. While fetal heart rate monitoring may later show distress, the characteristic sign among these options is the uterus with elevated resting tone. Normal fetal heart rate, fewer or weaker contractions, or no changes don’t fit with the physiology of placental abruption. This situation requires prompt maternal–fetal assessment and preparation for potential delivery if distress or instability develops.