The placenta is an organ that develops in your uterus during pregnancy. This structure provides oxygen and nutrients to your growing baby and removes waste products from your baby's blood. The placenta attaches to the wall of your uterus, and your baby's umbilical cord arises from it.During pregnancy, the most common placental problems include placental abruption, placenta previa and placenta accreta. These conditions can cause potentially heavy vaginal bleeding. After delivery, retained placenta is also sometimes a concern.Various factors can affect the health of the placenta during pregnancy like Maternal age,Premature rupture of the membranes,High blood pressure,Twin or other multiple pregnancy,Abdominal trauma,Substance abuse,Previous placental problems,Previous uterine surgery, and even Blood-clotting disorders.