Which statement best defines placenta previa?

• A. Placenta implants normally, supporting a typical delivery.
• B. Placenta implants improperly, partially or completely covering the cervical opening.
• C. Placenta detaches early from the uterine wall.
• D. Placenta attaches to the outer surface of the uterus after labor begins.

Answer: (B)

Placenta previa occurs when the placenta implants in the lower part of the uterus, partially or completely covering the cervical opening. This description matches the idea of the placenta implanting improperly near or over the cervix, which is why it’s the best definition. The other statements describe a normally implanted placenta, a placental detachment before delivery, or placentation on the outer uterine surface after labor has begun, none of which define placenta previa. In practice, placenta previa typically presents as painless vaginal bleeding in the third trimester, and management emphasizes avoiding vaginal exams, monitoring, and preparing for possible cesarean delivery if the previa persists. In the EMS setting, recognize the painless late-pregnancy bleeding as a potential placenta previa and ensure stabilization and rapid transport to obstetric care.