Which risk factor is associated with a higher likelihood of placenta previa?

The risk factor associated with a higher likelihood of placenta previa is past cesarean sections. A history of cesarean deliveries increases the risk because the surgical scar on the uterus can affect the implantation of the placenta in subsequent pregnancies. When the placenta attaches near or over the cervix, this is termed placenta previa. As the uterus expands during pregnancy, the abnormal location can lead to significant complications, including hemorrhage during delivery.

Other factors, while relevant in different contexts, do not have the same direct correlation with the occurrence of placenta previa. Increased physical activity does not directly impact placental implantation. Low folic acid intake is more closely associated with neural tube defects than with placenta previa, and young maternal age generally poses different risks in pregnancy, such as an increased likelihood of having a preterm birth, rather than a higher incidence of placenta previa. Thus, the association of past cesarean sections with placenta previa stands out clearly as a significant risk factor.