Placenta Previa
Overview
Plain-Language Overview
Placenta previa is a condition during pregnancy where the placenta grows in the lower part of the uterus, covering or being very close to the cervix, which is the opening to the birth canal. This affects the reproductive system and can cause painless, bright red vaginal bleeding during the second or third trimester. Because the placenta blocks the baby's exit, it can complicate delivery and may require special medical care. The condition can lead to risks for both the mother and baby, including premature birth and bleeding complications. Monitoring and diagnosis are important to manage the health of both mother and child.
Clinical Definition
Placenta previa is defined as the abnormal implantation of the placenta in the lower uterine segment, partially or completely covering the internal cervical os. This condition results from defective placental migration or implantation too close to the cervix, often associated with prior uterine surgery, multiparity, or advanced maternal age. The major clinical significance lies in its potential to cause painless third-trimester bleeding, which can lead to maternal hemorrhage and fetal compromise. It is a leading cause of antepartum hemorrhage and may necessitate cesarean delivery to prevent catastrophic bleeding during labor. Diagnosis and management focus on preventing maternal and fetal morbidity and mortality.