Match each clinical presentation of a third-trimester obstetric complication with its most likely diagnosis.
- A gravid patient at 36 weeks gestation experiences a sudden onset of unprovoked, bright red vaginal bleeding without abdominal pain; examination reveals a soft, non-tender uterus.Placenta previa
- A gravid patient at 38 weeks gestation presents with constant, severe abdominal pain and dark vaginal bleeding accompanied by a rigid, hypertonic uterus.Placental abruption
- A gravid patient at 39 weeks gestation develops painless vaginal bleeding immediately following spontaneous rupture of membranes, which is rapidly followed by fetal bradycardia.Vasa previa
- A gravid patient with a history of two prior cesarean deliveries experiences sudden tearing pelvic pain, sudden cessation of uterine contractions, and loss of fetal station.Uterine rupture
Answer
The presentations correctly match as follows: Painless bleeding matches Placenta previa; Painful bleeding with rigid uterus matches Placental abruption; Bleeding post-membrane rupture with fetal bradycardia matches Vasa previa; Sudden pain with loss of fetal station matches Uterine rupture.
Each obstetric complication has a distinct diagnostic signature. Placenta previa presents with painless bleeding. Placental abruption presents with painful bleeding and a tense uterus. Vasa previa uniquely presents with bleeding concurrent with membrane rupture and rapid fetal decompensation. Uterine rupture is distinguished by severe pain, loss of station, and a history of uterine scarring.
Step-by-Step Solution
Key Concept
Differentiating third-trimester obstetric bleeding etiologies relies on assessing the presence or absence of maternal pain, uterine tone, timing relative to membrane rupture, and fetal status.