How Placenta Previa Influences the Type and Timing of DeliveryPlacenta previa occurs when the placenta settles unusually low in the uterus and lies near or directly over the cervix. Since the cervix is the pathway your baby uses during labour, a low placenta often changes both the method and timing of delivery. When you understand the symptoms to expect, risks to watch for, and how your doctor plans your birth, the entire experience becomes less overwhelming and far more manageable.