Pregnancy Trauma Follow-up

Updated: May 12, 2015
  • Author: Andrew K Chang, MD, MS; Chief Editor: Bruce M Lo, MD, MBA, CPE, RDMS, FACEP, FAAEM, FACHE  more...
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Complications of pregnancy trauma include the following:

  • Exsanguination: Dramatic increases in uterine blood flow (60 to 600 mL/min) may result in rapid exsanguination if there is avulsion of the uterine vessels or rupture of the uterus.

  • Retroperitoneal hemorrhage: A common complication of pelvic fracture due to the tremendous increase in vascularity resulting from pregnancy.

  • Uterine rupture: Enlargement of the uterus makes it susceptible to direct abdominal trauma. This rare complication is estimated to complicate 0.6% of traumatic injury. Uterine rupture is associated with a fetal mortality rate approaching 100%. Maternal mortality of 10% is usually a result of associated injuries.

  • Rupture of amniotic membranes can lead to chorioamnionitis, preterm labor, and cord prolapse.

  • Amniotic fluid embolism (may lead to acute respiratory distress syndrome)

Placental abruption

Placental abruption is the most feared complication in cases of trauma. It occurs in 38-66% of major injuries and in 2-4% of minor injuries. It is the most common cause of fetal death when the mother survives the trauma. Placental abruption may be delayed for as long as 24-48 hours after the traumatic incident.

Diagnosis is made with 2 of the following 3 criteria:

  • Tense abdomen with uterine hypotonia

  • Maternal hypertension or hypotension

  • Ultrasonographic evidence of abruptio

Fetal distress is the most reliable indicator of active or impending abruption.

Ultrasonography is an insensitive tool and causes more than 50% of abruptions to be missed. Amniocentesis can be used to make the ultimate diagnosis in desperate situations.

Abruption can lead to consumptive coagulopathy. Fetal injury is the leading cause of fetal death in cases of maternal death. Direct fetal trauma is rare because of the protection from the uterus and amniotic fluid.

Fetomaternal hemorrhage

Historically, fetomaternal hemorrhage has been reported to occur in 9-30% of cases. However, one study of 151 women found an incidence of only 2.6%, which is similar to that of the general population.



Penetrating injury has a perinatal mortality rate of 40-70%, although the maternal mortality rate is less than that in the nonpregnant patient because of the protective effects of the large, muscular uterus on the maternal visceral organs.

In one urban study, violence accounted for 57% of maternal deaths (48% homicides, 9% suicides).

Investigators in another study reported a 7% maternal mortality rate in serious automobile injuries and a 14% injury rate in surviving mothers.