What happens during premature separation of Placenta?
Written by Glenn Rosenberg
Placenta abruptio during pregnancy is a condition in which the placenta, also known as the afterbirth, separates from the womb before the fetus is born. The placenta is a disc-shaped organ that provides nourishment and blood to a fetus. This most common form of this condition occurs in about 1 out of 150 deliveries. The severe form occurs in only 1 out of 500 to 750 births.
What is going on in the body?
In the normal birthing process, the placenta does not detach from the womb until after the infant is born. In placenta abruptio, blood vessels rupture and create a mass of blood, also called a hematoma. This hematoma shears off the blood vessels next to it, creating further bleeding and separation of the placenta.
There are two kinds of placenta abruptio, relating to where the bleeding occurs:
- Concealed. This form means that bleeding occurs within the uterus and does not leave the cervix.
- External. In this form, blood drains through the cervix and out of the body.
What are the causes and risks of the condition?
It may not be easy to tell what caused placenta abruptio. In fact, doctors can detect an exact cause in less than 5 out of 100 cases. Some causes (though rare) can include:
- abdominal trauma from an automobile accident or a fall
- sudden loss in size of the uterus, due to loss of amniotic fluid, or delivery of a first twin
- abnormally short umbilical cord
However, a woman is more at risk for this condition if she:
- has had this condition before
- has preeclampsia, which is a condition that develops during pregnancy as a result of hypertension
- has eclampsia, which is toxemia during pregnancy that becomes severe
- has chronic high blood pressure
- is older
- has uterine distension from multiple pregnancies, or an excess of amniotic fluid
- has had more than four children
- has diabetes
- has other medical conditions, such as systemic lupus erythematosus
- smokes cigarettes
- has more than 14 alcoholic drinks per week
- uses cocaine
- has a history of an attempted internal version, a procedure in which the obstetrician tries changing the baby's position from breech to head first.
What are the signs and symptoms of the condition?
Symptoms may vary, depending on:
- how much of the placenta has detached
- during which stage of pregnancy it occurs
Thirty percent of placenta abruptios are small and produce no symptoms. When the case is severe, symptoms may include:
- vaginal bleeding
- severe abdominal pain, which is different from uterine contractions
- uterus is tender and contracted tightly
- fetal distress, detected by fetal monitoring
- constant contractions, called uterine tetany
- back pain
- uterine tenderness
- maternal shock, with low blood pressure and inadequate blood flow to vital organs
This condition is sometimes confused with placenta previa.