Why does retained placenta cause heavy bleeding after birth?

After the baby is born, the placenta normally separates from the uterine wall and is delivered. Retained placenta means that all or part of it remains inside the uterus. A small fragment may be difficult to see when the placenta is examined, while a placenta that has not separated may remain attached.

The uterus usually contracts after delivery. This contraction compresses the open blood vessels at the attachment site. Retained tissue can interfere with this process, so the uterus may stay softer and bleeding may continue or become heavier. Bleeding can happen soon after birth or appear later, sometimes with clots, increasing pelvic pain, fever, or an unpleasant-smelling discharge. Other causes of heavy postpartum bleeding are also possible, including a poorly contracted uterus, tears, or clotting problems.

Tell the maternity team promptly if bleeding is heavier than expected, if clots are large or repeated, or if you feel faint or unwell. A clinician may assess your pulse, blood pressure, temperature, blood loss, and the firmness of your uterus. They may examine the placenta, perform an abdominal or vaginal examination, and use ultrasound when retained tissue is suspected.

Treatment depends on how much bleeding is happening and whether tissue remains. Care may include medicines that help the uterus contract, fluids through a vein, removal of retained tissue by a clinician, and treatment for infection when indicated. If bleeding is severe, hospital teams can provide monitoring and additional emergency treatment. Do not insert anything into the vagina or drive yourself if you feel weak, dizzy, or short of breath.

Heavy bleeding after birth needs urgent medical assessment, especially when it is sudden or increasing. Call emergency services or go to an emergency department if you are soaking pads quickly, passing repeated large clots, feeling faint or confused, having trouble breathing, developing a racing heartbeat, or becoming pale, cold, or very weak. Ask someone to stay with you while help is arranged.

Contact your maternity unit urgently for bleeding that returns or becomes heavier after it had started to settle, or for fever, worsening lower-abdominal pain, or foul-smelling discharge. These symptoms can point to retained tissue or infection and should not be managed at home without assessment.

You could ask: What might be causing my bleeding? Does my examination suggest retained placental tissue? Would an ultrasound help? Which treatment do you recommend, and what warning signs should bring me back? If tissue is removed, ask how to care for yourself afterwards and when you should have a follow-up review.