Women who give birth are prepared for the bleeding that follows. It is a normal, natural part of the birthing process and continues for a period of a few days up to a few weeks. And even after that, lighter bleeding is not uncommon for up to a month. This is postpartum bleeding, the discharge of blood and tissue from a woman’s vagina, also known in medical terminology as lochia. And since the normal blood volume in a woman’s body can grow by up to fifty percent during pregnancy, a small amount of bloodloss after the birth will not be harmful. But what causes lochia? Why does bleeding occur postpartum?
After a woman has given birth, her body naturally expels the placenta, which was attached to the walls of her uterus during the baby’s development. The tissue underneath the placental implantation site heals and pushes the placenta away causing the placenta to come away as part of the lochia. This allows a woman to have any number of future pregnancies, since the process does not create a scarring and leaves the uterus ready for another placenta to attach when or if the woman becomes pregnant again. However, it also leaves open blood vessels that bleed into the uterus. Tearing of the vagina, or an episiotomy, will also add to the bleeding until it is stitched closed.
The uterus then undergoes a process called involution, which is the process of the uterus shrinking. This contracting helps close off many of the blood vessels that would otherwise continue to bleed. Involution normally occurs very quickly. But if this process does not go as it should, heavy bleeding may continue, or irregular bleeding may be experienced. Abnormal involution can be caused by an infection, or when a piece of the placenta remains unexpelled. The bleeding will most likely expel any remaining chunks of the placenta on its own and the situation will resolve itself that way. However if it does not the doctor may elect to do a “dilate and clean” procedure, or D&C, to correct the problem.
Bleeding will be heavy and bright red for the first few days after childbirth and become less after that. Although there may be spotting for the next few weeks after that, there should not be enough blood left in any discharge to notice by the end of the six week long post-partum time period. Toward the end of this time, the discharge will be white or light yellow, made up primarily of white blood cells. The process of involution can be helped along by massage techniques or by taking synthetic oxytocin. Oxytocin is a hormone that encourages the uterus to shrink after pregnancy. Breastfeeding releases natural oxytocin in the woman’s body which also aids involution.
During lochia any bleeding that is heavier than a normal menstrual period’s should be brought to the attention of a doctor. This includes the passing of any large clots of blood. Continued bleeding of this type can indicate a problem or an infection. Tenderness associated with bleeding is not normal, and also may indicate a problem. Bloody discharge that has an odor is likewise abnormal. Any of these symptoms should be discussed with a doctor during the scheduled follow-up visit, if not sooner.