Final answer:
Excessive vaginal bleeding post-delivery can be caused by uterine atony, retained placenta, cervical laceration, or uterine rupture, all of which require immediate medical attention.
Step-by-step explanation:
The cause of excessive vaginal bleeding post-delivery can include several conditions. The most common causes are uterine atony, where the uterus does not contract effectively after delivery, retained placenta, where parts of the placenta remain in the uterus after childbirth leading to postpartum hemorrhage, and cervical laceration, which involves tears in the cervix due to childbirth. Uterine rupture is a less common but very serious cause and occurs when the muscular wall of the uterus tears during childbirth.
After delivery, the period known as the postpartum period involves several biological changes. Normal postpartum vaginal discharge, termed lochia, transitions from lochia rubra to lochia serosa, and later to lochia alba over several weeks. Excessive bleeding beyond the expected amount of lochia can signal complications and should be addressed by a healthcare professional immediately.