placental abruption


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Placental Abruption

 

Definition

Placental abruption occurs when the placenta separates from the wall of the uterus prior to the birth of the baby. This can result in severe, uncontrollable bleeding (hemorrhage).

Description

The uterus is the muscular organ that contains the developing baby during pregnancy. The lowest segment of the uterus is a narrowed portion called the cervix. This cervix has an opening (the os) that leads into the vagina, or birth canal. The placenta is the organ that attaches to the wall of the uterus during pregnancy. The placenta allows nutrients and oxygen from the mother's blood circulation to pass into the developing baby (the fetus) via the umbilical cord.
During labor, the muscles of the uterus contract repeatedly. This allows the cervix to begin to grow thinner (called effacement) and more open (dilatation). Eventually, the cervix will become completely effaced and dilated, and the baby can leave the uterus and enter the birth canal. Under normal circumstances, the baby will go through the mother's vagina during birth.
During a normal labor and delivery, the baby is born first. Several minutes to 30 minutes later, the placenta separates from the wall of the uterus and is delivered. This sequence is necessary because the baby relies on the placenta to provide oxygen until he or she begins to breathe independently.
Placental abruption occurs when the placenta separates from the uterus before the birth of the baby. Placental abruption occurs in about one out of every 200 deliveries. African-American and Latin-American women have a greater risk of this complication than do Caucasian women. It was once believed that the risk of placental abruption increased in women who gave birth to many children, but this association is still being researched.

Causes and symptoms

The cause of placental abruption is unknown. However, a number of risk factors have been identified. These factors include:
  • older age of the mother
  • history of placental abruption during a previous pregnancy
  • high blood pressure
  • certain disease states (diabetes, collagen vascular diseases)
  • the presence of a type of uterine tumor called a leiomyoma
  • twins, triplets, or other multiple pregnancies
  • cigarette smoking
  • heavy alcohol use
  • cocaine use
  • malformations of the uterus
  • malformations of the placenta
  • injury to the abdomen (as might occur in a car accident)
Symptoms of placental abruption include bleeding from the vagina, severe pain in the abdomen or back, and tenderness of the uterus. Depending on the severity of the bleeding, the mother may experience a drop in blood pressure, followed by symptoms of organ failure as her organs are deprived of oxygen. Sometimes, there is no visible vaginal bleeding. Instead, the bleeding is said to be "concealed." In this case, the bleeding is trapped behind the placenta, or there may be bleeding into the muscle of the uterus. Many patients will have abnormal contractions of the uterus, particularly extremely hard, prolonged contractions. Placental abruption can be total (in which case the fetus will almost always die in the uterus), or partial.
Placental abruption can also cause a very serious complication called consumptive coagulopathy. A series of reactions begin that involve the elements of the blood responsible for clotting. These clotting elements are bound together and used up by these reactions. This increases the risk of uncontrollable bleeding and may contribute to severe bleeding from the uterus, as well as causing bleeding from other locations (nose, urinary tract, etc.).
Placental abruption is risky for both the mother and the fetus. It is dangerous for the mother because of blood loss, loss of clotting ability, and oxygen deprivation to her organs (especially the kidneys and heart). This condition is dangerous for the fetus because of oxygen deprivation, too, since the mother's blood is the fetus' only source of oxygen. Because the abrupting placenta is attached to the umbilical cord, and the umbilical cord is an extension of the fetus' circulatory system, the fetus is also at risk of hemorrhaging. The fetus may die from these stresses, or may be born with damage due to oxygen deprivation. If the abruption occurs well before the baby was due to be delivered, early delivery may cause the baby to suffer complications of premature birth.

Diagnosis

Diagnosis of placental abruption relies heavily on the patient's report of her symptoms and a physical examination performed by a health care provider. Ultrasound can sometimes be used to diagnose an abruption, but there is a high rate of missed or incorrect diagnoses associated with this tool when used for this purpose. Blood will be taken from the mother and tested to evaluate the possibility of life-threatening problems with the mother's clotting system.

Treatment

The first line of treatment for placental abruption involves replacing the mother's lost blood with blood transfusions and fluids given through a needle in a vein. Oxygen will be administered, usually by a mask or through tubes leading to the nose. When the placental separation is severe, treatment may require prompt delivery of the baby. However, delivery may be delayed when the placental separation is not as severe, and when the fetus is too immature to insure a healthy baby if delivered. The baby is delivered vaginally when possible. However, a cesarean section may be performed to deliver the baby more quickly if the abruption is quite severe or if the baby is in distress.

Prognosis

The prognosis for cases of placental abruption varies, depending on the severity of the abruption. The risk of death for the mother ranges up to 5%, usually due to severe blood loss, heart failure, and kidney failure. In cases of severe abruption, 50-80% of all fetuses die. Among those who survive, nearly half will have lifelong problems due to oxygen deprivation in the uterus and premature birth.

Prevention

Some of the causes of placental abruption are preventable. These include cigarette smoking, alcohol abuse, and cocaine use. Other causes of abruption may not be avoidable, like diabetes or high blood pressure. These diseases should be carefully treated. Patients with conditions known to increase the risk of placental abruption should be carefully monitored for signs and symptoms of this complication.

Resources

Organizations

American College of Obstetricians and Gynecologists. 409 12th Street, S.W., P.O. Box 96920, Washington, DC 20090-6920.

Key terms

Cesarean section — Delivery of a baby through an incision in the mother's abdomen, instead of through the vagina.
Labor — The process during which the uterus contracts, and the cervix opens to allow the passage of a baby into the vagina.
Placenta — The organ that provides oxygen and nutrition from the mother to the baby during pregnancy. The placenta is attached to the wall of the uterus and leads to the baby via the umbilical cord.
Umbilical cord — The blood vessels that allow the developing baby to receive nutrition and oxygen from its mother; the blood vessels also eliminate the baby's waste products. One end of the umbilical cord is attached to the placenta and the other end is attached to the baby's belly button (umbilicus).
Uterus — The muscular organ that contains the developing baby during pregnancy.
Vagina — The birth canal; the passage from the cervix of the uterus to the opening leading outside of a woman's body.

placental abruption

placental abruption

A popular, widely used term for abruptio placentae.

pla·cen·tal ab·rup·tion

(plă-sen'tăl ab-rŭp'shŭn)
Premature separation of a normally situated placenta from the uterine wall after the 20th week of gestation.
References in periodicals archive ?
The RII was largest for placental abruption, followed by "other causes", while the SII was greatest for "other causes", followed by placental abruption and unspecified causes.
Our work shows a link between anti-TPO antibodies and placental abruption, but that does not necessarily mean that thyroid supplementation would improve the health of the women or babies," said Dr.
You can reduce your risk of placental abruption by avoiding smoking tobacco, controlling high blood pressure and other chronic conditions and using a seat belt whenever you're in a car to minimise potential trauma Placenta previa is another complication that can cause excessive bleeding before
However, disseminated intravascular coagulation (DIC), placental abruption and fetal death contribute to the significant maternal and fetal morbidity and mortality involved with the condition (3).
In a study including 64 newborns of women with one or more of the following pregnancy complications: pre eclampsia, placental abruption and intrauterine growth retardation, the maternal and neonatal blood was screened for heritable thrombophilic mutations.
Facing this problem in our current study, we have decided to focus on the incidence of three complications to maternal health identified in the medical literature as potentially preventable by prenatal care: placental abruption, pregnancy-associated hypertension, and anemia.
Lindermann reached a differential diagnosis of pubic symphysis pain, bladder pain, labor, or placental abruption.
For example, a negligent resuscitation following a properly diagnosed and treated placental abruption may leave you with an incremental injury that is difficult, if not impossible, to define.
Placental abruption observed later in the pregnancy was also excluded as a possible source of feto-maternal hemorrhage.
Reproductive consequences compared with vaginal birth include increased infertility, (16) miscarriage, (15) placenta previa (placenta overlays the cervix), (19) placental abruption (the placenta detaches partially or completely before the birth), (19) and premature birth.
I read that the Countess of Wessex had to have an emergency Caesarean section because she had a placental abruption.
In a study of over 25,000 women, those who had a Caesarean section were three to four times more likely during a later pregnancy to develop a potentially serious bleeding condition known as placental abruption - in which the placenta detaches from the uterus before delivery - than women who had never had the procedure.