Question

An 18-year-old G1 woman at 32 weeks gestation presents with severe abdominal pain and a small amount of bleeding. She has received routine prenatal care, smokes one pack of cigarettes per day and admits to using crack cocaine. On exam, her blood pressure is 140/80, pulse 100 and she is afebrile. Her uterus is tense and very tender. Pelvic ultrasound reveals a fundal placenta, cephalic presentation of the fetus and no other abnormalities. Cervical examination reveals blood coming through the os and is one centimeter dilated. Fetal heart tones have a baseline of 160s, with a category III tracing. What is the most likely diagnosis?

1) Placenta previa
2) Premature rupture of the membranes
3) Preterm labor
4) Placental abruption
5) Chorioamnionitis

Answer 1

The severe pain, uterine tenderness, and fetal distress point to a diagnosis of placental abruption, especially given the patient's risk factors, including substance use.

Step-by-step explanation:

The presentation of severe abdominal pain and a small amount of bleeding at 32 weeks gestation, with a tense and very tender uterus, and the ultrasound findings of a fundal placenta with a cephalic presentation of the fetus, make placental abruption the most likely diagnosis. Placental abruption occurs when the placenta detaches from the uterine wall before delivery, which can cause the described symptoms. The small amount of bleeding through the os and the category III fetal heart tracing (which indicates severe fetal distress) are also consistent with this diagnosis. Pregnancy complications such as those associated with tobacco and crack cocaine use can increase the risk of placental abruption.