A 19-year-old woman, gravida 2 para 1, at 38 weeks gestation comes to the emergency department due to severe abdominal pain and vaginal bleeding. The patient had an ultrasound at 8 weeks gestation for vaginal spotting but has not otherwise received prenatal care this pregnancy. Her prior pregnancy two and a half years ago ended in a classical cesarean delivery at 24 weeks gestation for placental abruption. The patient smokes a pack of cigarettes daily and uses cocaine multiple times a week. Blood pressure is 90/60 mm Hg and pulse is 130/min. The abdomen is tender and has an irregular mass; no contractions are palpated. Bright red blood is noted on the perineal pad. Fetal heart tracing shows multiple prolonged decelerations to 100/min. Which of the following risk factors most likely contributed to this patient's presentation?

Question

A 19-year-old woman, gravida 2 para 1, at 38 weeks gestation comes to the emergency department due to severe abdominal pain and vaginal bleeding.  The patient had an ultrasound at 8 weeks gestation for vaginal spotting but has not otherwise received prenatal care this pregnancy.  Her prior pregnancy two and a half years ago ended in a classical cesarean delivery at 24 weeks gestation for placental abruption.  The patient smokes a pack of cigarettes daily and uses cocaine multiple times a week.  Blood pressure is 90/60 mm Hg and pulse is 130/min.  The abdomen is tender and has an irregular mass; no contractions are palpated.  Bright red blood is noted on the perineal pad.  Fetal heart tracing shows multiple prolonged decelerations to 100/min.  Which of the following risk factors most likely contributed to this patient's presentation?

Quizplus · Accepted Answer

11ec25c8_da93_d180_bc81_3b247e72ee6b_MD0003_00 This patient's presentation is most consistent with uterine rupture, a full-thickness disruption of the uterine wall. Uterine rupture can present with severe, sudden-onset abdominal pain and vaginal bleeding; patients may have a palpable, irregular abdominal mass (ie, protruding fetal parts) and fetal decelerations due to fetal hypoxia and cord compression. Additional findings may include loss of fetal station and change in contraction pattern (eg, decreased uterine tone). Uterine rupture is an obstetric emergency because of the high risk of fetal demise and maternal hemorrhagic shock, as in this patient. Uterine rupture A significant risk factor for uterine rupture is prior uterine surgery, particularly a prior classical cesarean delivery because it creates a scar in the upper uterus (ie, near the fundus). The myometrium in the upper uterus is thick and contracts forcefully during labor. In patients with a prior classical cesarean delivery, the inelastic scar may not withstand increasing uterine distension or labor contractions, resulting in uterine rupture. Treatment of uterine rupture is with emergent laparotomy and cesarean delivery. inelastic scar (Choice A) First-trimester bleeding can occur due to a subchorionic hematoma, in which the chorion partially detaches from the uterus due to bleeding. Although this increases the risk of early pregnancy loss, it does not increase the risk of uterine rupture. subchorionic hematoma (Choice B) Tobacco and cocaine use increases the risk of abruptio placentae via vasoconstriction, resulting in placental ischemia, infarction, and premature placental separation from the uterus. Although abruptio placentae can cause abdominal pain, vaginal bleeding, and fetal bradycardia, it is not associated with an irregular abdominal mass. In addition, neither tobacco nor cocaine increases the risk of uterine rupture. abruptio placentae (Choice C) A short interpregnancy interval (eg, <6-18 months from last delivery) may increase the risk of uterine rupture due to insufficient time for uterine healing in patients who underwent cesarean delivery. This patient's last delivery was two and a half years ago, making this a less likely risk factor. (Choice D) Maternal age ≥35 may increase the risk of uterine rupture. This patient is age 19. Educational objective: Prior uterine surgery, particularly prior classical cesarean delivery, is a significant risk factor for uterine rupture, which can present with sudden-onset abdominal pain, vaginal bleeding, fetal decelerations, and an irregular abdominal mass (ie, protruding fetal parts). References: Optimal timing and mode of delivery after cesarean with previous classical incision or myomectomy: a review of the data. (http://www.ncbi.nlm.nih.gov/pubmed/21962624) ACOG practice bulletin no. 205: vaginal birth after cesarean delivery. (http://www.ncbi.nlm.nih.gov/pubmed/30681543)

A 19-Year-Old Woman, Gravida 2 Para 1, at 38 Weeks