Placenta previa is a condition where the placenta attaches to the uterus either partially or completely covering the interior opening of the cervix.
The placenta is the organ that supports your baby while it is growing.
The umbilical cord runs from the baby to the placenta and carries nutrients, oxygen and waste products.
Your placenta and the umbilical cord are literally your baby’s life line. Anything that compromises the health of the placenta can compromise your baby.
Risk factors for placenta previa include having previously a Cesarean section, or previous placenta previa.
Previous uterine surgery can increase your risk of having placenta previa, as can smoking or using cocaine. Most of the time placenta previa is something that just happens. There is generally nothing the mother-to-be has or has not done that could have caused it to happen.
Your health care provider will note the placement of your placenta during ultrasounds. If you have a partial or complete placenta previa, your health care provider will perform routine ultrasounds to note the placement and health of your placenta.
Placenta previa is fairly common in early pregnancy, but usually resolves on its own with no problems. As the uterus grows and expands to accommodate your growing pregnancy, a placenta that was attached in the lower segment of the uterus near the cervix will move up and away from the cervix.
A placenta that was partially over the cervix may move away from the cervix entirely as the pregnancy continues.
The problem arises when the placenta does not move up and away from the cervix. During labor and delivery, the cervix completely thins out (effaces) and opens (dilates) to allow the baby to be born.
If the placenta is attached in the lower portion of the uterus or over the cervix, it has nowhere to go and becomes detached from the uterine wall. This is known as a placental abruption, and it can be extremely serious for both mom and her baby.
If only a very small portion of the placenta is involved in the placenta previa, a mother may be able to labor and deliver normally. However, she will be monitored very closely for signs of a placental abruption, which would necessitate an emergency Cesarean section.
If the placenta completely covers the internal opening of the cervix or a large portion of it, she will need a Cesarean delivery before or as soon as she goes into labor to prevent a placental abruption.