What is the treatment for placental abruption?

Usually delivery: While you can try to control bleeding and hypertension (eclamsia) in general, delivery is going to be the only true control of the problem.

Watching, waiting: Abruption is a bleed from the placenta; a disruption of either the mother or baby's blood supply. Many causes: trauma, high blood pressure, drugs (cocaine), preterm labor, polyhydramnios. Can be very large or very small, so even US can miss a diagnosis. Symptoms: usually preterm contractions, sometimes vaginal bleed. Fetal monitoring is necessary. Wait, watch; abruption can self-heal sometimes.

Simple really: Abruption is the separation of the placental attachment to the uterine wall prior to delivery.Whether on the margin, central, or both, the untreated outcome would have the baby bleeding out all its blood & dying. It is less likely to kill mom, but with complications both could be lost. Urgent delivery, by c-section is the expected treatment.