All women experience some bleeding after childbirth, whether they deliver vaginally or by cesarean section. Bleeding that's heavier than normal, called postpartum hemorrhage, occurs in 5 to 15 percent of women, according to the American Congress of Obstetricians and Gynecologists, also known as ACOG, and affects more women after cesarean birth than after vaginal delivery. Postpartum hemorrhage is classified as early, occurring within the first 24 hours after delivery, or late, occurring after 24 hours.
Definition
Normal blood loss after vaginal delivery is 500 ml, the Merck Manual states. After cesarean delivery, blood loss of up to 1,000 ml falls into the normal category. Abnormal bleeding, or postpartum hemorrhage, exceeds these limits. A 10 percent drop in hematocrit levels, which indicate the amount of red blood cells present, may also define abnormal bleeding, ACOG reports.
Causes
Abnormal bleeding after childbirth has many causes. The most common cause, the Children's Hospital of Wisconsin states, is uterine atony. This occurs when the uterine muscle fails to tighten and clamp down on blood vessels after delivery. Uterine atony occurs in one in 20 deliveries, ACOG says. Since as much as 600 ml of blood passes through the placenta every minute in pregnancy, a significant amount of blood loss takes place quickly.
Tissue laceration, retained placental fragments, hematoma and uterine rupture or inversion--in which the uterus turns inside out when the placenta delivers--all cause postpartum hemorrhage, Merck reports. A multiple pregnancy, uterine fibroids and rapid labor may predispose a woman to abnormal bleeding after delivery.
Symptoms
Symptoms of abnormal bleeding besides visual blood flow include pallor, rapid heartbeat, shortness of breath, weakness, fainting, low blood pressure and decreased urine volume, according to ACOG.
Treatment
Treatment varies depending on the cause. In uterine atony, medications that cause muscle contraction, such as oxytocin, are given intravenously to increase uterine tone and slow or stop bleeding. Packing the uterus puts pressure on bleeding vessels to slow blood loss. Intravenous fluids replace lost blood volume; blood products are necessary in some cases. Suturing lacerations and manual compression on hematomas also help stop hemorrhage. Uterine massage helps maintain uterine tone.
Complications
Severe blood loss can lead to uterine removal, or hysterectomy. This may become necessary if the placenta has grown deeper into the uterus than normal and can't be removed, a condition called placenta accreta, the American Pregnancy Association warns. Retained placenta fragments may make it necessary to perform uterine curettage, or scraping to remove the fragments. Severe blood loss can also lead to shock and maternal death if not promptly treated.
