What differentiates a complete placenta previa from a partial placenta previa?

A complete placenta previa is characterized by the placenta fully covering the cervical os, whereas a partial placenta previa involves the placenta only partially covering the cervical os. This distinction is crucial as it has significant implications for the management of the pregnancy and the mode of delivery. In cases of complete previa, there is a higher risk of hemorrhage during labor, and a cesarean delivery is usually recommended to ensure the safety of both the mother and the baby. This differentiation is based solely on the amount of cervical os that is covered by the placenta, making it key to understanding the potential complications and appropriate clinical interventions needed.

The other options do not serve as distinguishing factors between complete and partial placenta previa. Fetal position and maternal hypertension can be relevant in other contexts but do not specifically differentiate the type of placenta previa. Similarly, the timing of diagnosis does not inherently indicate whether the previa is complete or partial; it merely signifies when the condition is identified during the pregnancy.