In a pregnancy with multilobate placenta and velamentous cord insertion at 21 weeks, what fetal complication is the patient at greatest risk for?

• A. Vasa previa
• B. Placental abruption
• C. Preeclampsia
• D. Fetal growth restriction

Answer: (A)

Velamentous cord insertion places the umbilical vessels in the membranes before they reach the placental disk, leaving them exposed and vulnerable. When the placenta is multilobate, some of these vessels course between lobes and can cross the cervical os. If membranes rupture or during labor, those exposed vessels can tear and cause rapid fetal hemorrhage. This makes vasa previa the most dangerous fetal complication in this setting. Other issues like placental abruption, preeclampsia, or fetal growth restriction are possible in pregnancy but do not explain the immediate and life-threatening risk posed by torn exposed vessels over the os.