Placental abruption

Question 1

Definition and incidence of placental abruption?

Answer 1

Premature separation of a normally implanted placenta

1% of US births, 50% of abruptions occur before 37w

Question 2

Risk factors for placental abruption?

Answer 2

Increasing maternal age, increasing parity, cigarette smoking, cocaine use, hypertensive disorders, premature rupture of membranes, chorioamnionitis, multiple gestations, maternal trauma, uterine factors (Mullerian anomalies, leiomyomas), subchorionic hematoma in early pregnancy (confirmed by ultrasound), previous abruption in another pregnancy (risk up by 10-20x)

Question 3

Signs and symptoms of abruption?

Answer 3

Vaginal bleeding, abdominal pain, increased uterine tone with frequent contractions, preterm labor

No bleeding does NOT mean no abruption - could just be bleeding into the myometrium

FHR hints: bradycardia, sinusoidal pattern, reduced variability, recurrent decelerations

Question 4

Maternal risks and fetal risks of abruption?

Answer 4

Maternal: hemorrhage, hypovolemia, hemorrhage-associated complications (shock, coagulopathy, renal failure)

Fetal: preterm birth, stillbirth, neurological complications (intraventricular hemorrhage, periventricular leukomalacia)

Question 5

Definition of Couvelaire uterus?

Answer 5

Blood dissects into myometrium and predisposes patient to uterine atony

Question 6

A 22-year-old primigravid woman at 31 weeks of gestation was admitted 5 days ago for preterm premature rupture of membranes. She is receiving antibiotics for latency and has completed a course of steroids. Her past medical history is negative. She smokes a half pack of cigarettes daily, but has been switched to a nicotine patch during the hospital stay. She now reports vaginal bleeding. When questioned, she reports that the baby is “balling up.” Her heart rate is 110 beats per minute, blood pressure 130/80 mm Hg, and temperature 37.2°C (99.0°F). Fetal heart rate is 160 beats per minute with minimal variability. On abdominal examination, her uterus is continuously firm to palpation. Given this clinical scenario, the most likely diagnosis is:

(A) placenta previa
(B) preterm labor
(C) placental abruption
(D) chlamydial cervicitis

Answer 6

(C) placental abruption