Many complications can accompany pregnancy and delivery, but only a few emergencies warrant significant concern. Placental abruption, while rare, is one such emergency. What is an abruption, and what are the risks? Let's explore what can you expect in the hospital, what the potential outcomes are, and how an abruption can be prevented.
An abruption is the separation of the placenta from the wall of the uterus before delivery.
Severity of the abruption and gestational age are the greatest determinants for the outcome of parent and baby.
Many factors can put a pregnant parent at risk for an abruption.
Consequences of abruption can significantly impact the well-being of the pregnant parent and baby.
What is a placental abruption?
A placental abruption is when the placenta detaches from the inner lining of the uterus before the birth of your baby. The placenta is responsible for nutrient and oxygen transfer via blood. Detachment of the placenta directly interrupts this flow between you and your baby, thus causing significant problems for both. Placental abruption or 'abruptio placentae' can be a rare obstetric emergency that affects about 1% of pregnancies. Most abruptions occur before 37 weeks of pregnancy, though not always. It is the leading cause of maternal obstetric illness and fetal death.
Signs and symptoms
The separation of the placenta from the uterine wall can be partial or complete. The tearing away of blood vessels causes bleeding on the maternal side of the placenta. This bleeding can be internal and hidden or external and exiting the body. There are four types of placental abruption based on signs and symptoms:
Asymptomatic (class 0)
Partial separation from uterine wall, no symptoms, discovery of a blood clot on the maternal side of the placenta following delivery.
Mild (class 1)
Partial separation from uterine wall, none or minor vaginal bleeding, mild uterine tenderness normal vital signs, no fetal distress.
Moderate (class 2)
Complete separation from uterine wall, none to moderate vaginal bleeding, significant uterine tenderness with unending contraction, vital sign changes, fetal distress is present, blood lab changes.
Severe (class 3)
Complete separation from uterine wall, none to heavy vaginal bleeding, a contracted uterus that does not relax, vital signs that indicate the patient is in shock, blood lab changes, fetal death.
Who is at risk for a placental abruption?
The exact cause of this rare complication is not known. Placental abruption risk factors fall into three categories:
- Health history. Smoking, cocaine use during pregnancy, history of a placental abruption, pregnant parent over age 35, high blood pressure.
- Current Pregnancy. Preeclampsia, multiple gestation pregnancy such as twins, triplets, an increased amount of amniotic fluid called polyhydramnios. This can occur in gestational diabetes. Short umbilical cord, sudden uterine decompression. Examples include water breaking with polyhydramnios or delivery of a first twin.
- Abdominal trauma. Motor vehicle accident, falls, violent encounter.
Treatment for a placental abruption
Placental abruptions are often immediate, unexpected, and life-threatening for the parent and baby. It is vital to contact your obstetrician or midwife if you notice the following:
- Vaginal bleeding. Some amount of non-worrisome vaginal bleeding may occur during pregnancy. But, it is important to be cautious and speak with your healthcare provider.
- Contraction or severe abdominal pain that does not go away. Placental abruption can occur without vaginal bleeding.
Your healthcare provider will direct you to report immediately to a hospital, potentially by ambulance, to be evaluated. Conversely, placental abruption can be discovered or occur while in labor. Either way, you and your baby will be assessed quickly.
If a placental abruption is suspected, many actions by the medical staff will happen rapidly to ensure your safety and your baby's health. Activities that may occur within the hospital include:
- Intravenous (IV) fluids
- Supplemental oxygen
- Continuous vital sign monitoring, especially blood pressure and heart rate
- Monitoring of fetal well-being
- Blood lab draws
- Medication administration
- Immediate delivery
Depending on your well-being, the status of your baby, and the gestation of your pregnancy, immediate delivery, vaginally or by cesarean, may be necessary to preserve life. The discovery of an asymptomatic or mild abruption may result in admission to the hospital for close observation and monitoring.
Risks of a placental abruption
Severe bleeding can lead to many complications for the pregnant parent, while lack of oxygen and, potentially, prematurity can greatly impact a newborn.
For the pregnant parent
Placental abruptions carry a high maternal illness or mortality rate that may require transfer to the intensive care unit for close monitoring, especially postpartum. Significant complications of placental abruption include:
- Severe bleeding. Severe bleeding requiring blood transfusions.
- Hysterectomy. Surgical removal of the uterus (hysterectomy).
- Bleeding disorders. Specifically, disseminated intravascular coagulopathy (DIC) as a result of overactive clotting factors resulting in small blood clots throughout the body.
- Kidney issues. Kidney failure.
- Cardiac events. Negative cardiac events.
- Death. 1 to 5% of patients in the United States.
For your baby
Placental abruption is life-threatening to your baby. The gestational age — number of weeks pregnant — and severity of the abruption determines your newborn's survival. Health risks to your newborn include:
- Preterm birth and low birth weight
- Birth asphyxia — the inability of the newborn to breathe at birth due to lack of oxygen during the birth process
- Cerebral palsy
- Cystic periventricular leukomalacia — damage to the white matter of the brain
- Brain hemorrhage
Respiratory distress syndrome (RDS)
- Neonatal death
Can a baby survive a placental abruption?
Sadly, a small number of babies, 15% according to the American Academy of Pediatrics, do not survive a placental abruption.
Due to the comorbidities associated with preterm delivery and birth asphyxia, the impact of placental abruption can extend well beyond the newborn period for surviving babies.
Can a placental abruption be prevented?
Placental abruptions cannot be predicted or prevented in most cases. But in some, recognizing the risk factors can help anticipate pregnancy complications. Smoking and cocaine use significantly impact the risk of placental abruption. Smoking cessation and drug counseling are highly recommended. Do not hesitate to speak with your obstetrician or midwife about available resources.
If a placental abruption occurs, your health outcome and that of your newborn depend on when you arrive at the hospital for evaluation and treatment. There, you will receive care to preserve the well-being of yourself and your unborn baby. Never hesitate to speak with your healthcare provider about concerning symptoms.