Placental abruption

Background

• Premature separation of placenta from uterus
• Usually occurs spontaneously but also associated w/ trauma (even minor trauma)
• Usually occurs at >15 weeks gestation
• Must be considered in pts who p/w painful vaginal bleeding near term
• Abruption may be complete, partial, or concealed
  • Amount of external bleeding may not correlate with severity

Risk Factors

1. HTN
2. Trauma
3. Smoking
4. Advanced maternal age
5. Prior placental abruption
6. Thrombophilia
7. Cocaine abuse
8. History of C-section or other uterine sx

Clinical Features

• Painful vaginal bleeding (may be absent if retroplacental)
  • Characteristically dark and the amount is often insignificant
  • But up to 20% have no vaginal bleeding or pain
• Severe uterine pain
• Uterine contractions
• Hypotension
• N/V
• Back pain
• Premature labor
• Fetal distress
• Increasing fundal height

Differential Diagnosis

Abdominal Pain in Pregnancy

The same abdominal pain differential as non-pregnant patients, plus:

<20 Weeks

• Ectopic pregnancy
• First trimester abortion
  • Complete abortion
  • Threatened abortion
  • Inevitable abortion
  • Incomplete abortion
  • Missed abortion
  • Septic abortion
• Round ligament stretching
• Incarcerated uterus
• Malposition of the uterus

>20 Weeks

• Labor/Preterm labor
• Placental abruption
• Placenta previa
• Vasa previa
• Uterine rupture
• Vaginal trauma
• HELLP syndrome
• Cholestasis of pregnancy
• Chorioamnionitis
• Incarcerated uterus
• Acute fatty liver of pregnancy
• Malposition of the uterus
• Placenta accreta
• Placenta increta
• Placenta percreta

Any time

• Hemorrhagic ovarian cyst
• Fibroid degeneration or torsion
• Ovarian torsion
• Constipation

Work-Up

• Type & Cross
• CBC
• Platelets
• PT/INR
• PTT
• Fibrinogen
• D-dimer
• Fibrin Degraded Products
• Pelvic US
  • Sp, not Sn (as low as 24% sensitive)
  • Cannot be used alone to rule-out placental abruption if negative
  • Can rule-out placenta previa
• If available, obtain fetal heart monitoring
• Consider Ultrasound: FAST if trauma

Treatment

• Fluid resuscitation
• Transfuse blood products (as needed)
• Emergent OB/GYN consult
  • If unavailable consider C-section in ED
• Consider minimum 6 hours observation even if abruption not identified, if mechanism is concerning

Complications

Maternal

• Hemorrhagic shock
• DIC
• Uterine rupture
• Multi-organ failure

Neonatal

• Neurodevelopmental abnormalities
• Death: 67 to 75% rate of fetal mortality

See Also

Vaginal Bleeding (Main)