Placental abruption is a condition that can occur during pregnancy, in which the placenta prematurely separates from the uterine wall. The condition can lead to severe health complications for the pregnant person and the fetus.

Placental abruption is a serious pregnancy complication that occurs when the placenta detaches from the uterus before delivery. It needs immediate medical attention.

The placenta is a temporary organ that forms during pregnancy. It connects the fetus to the uterus, provides oxygen and nutrients to the fetus through the umbilical cord, and removes waste from the fetus.

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In placental abruption, the placenta completely or partially separates from the uterine wall. This can prevent the fetus from receiving enough oxygen and can lead to several pregnancy complications.

The condition is rare, occurring in 0.6% to 1.2% of pregnancies. However, if a person suspects placental abruption, they should contact emergency health services as soon as possible.

The symptoms of placental abruption can differ between individuals.

The most common symptoms include abdominal pain and vaginal bleeding during the second half of pregnancy.

However, some people do not experience visible bleeding, as blood sometimes accumulates between the uterine wall and the placenta.

Other symptoms of placental abruption may include:

Several pregnancy conditions may cause similar symptoms. A person should contact a healthcare professional if they experience bleeding, pain, or any other symptoms during pregnancy.

When to seek emergency care

Placental abruption is a medical emergency that requires immediate treatment. The onset of the condition is typically sudden and severe, and can be life threatening to the pregnant person and the fetus.

If a person experiences any of the above symptoms of placental abruption in the third trimester, they should contact a healthcare professional, emergency medical services, or go to the hospital’s emergency department immediately.

There are no specific laboratory tests that doctors use to diagnose placental abruption. However, they may use several examination methods and tests to help eliminate other potential causes and gather enough information to make a diagnosis.

A doctor may begin by asking about and reviewing a person’s symptoms, medical history, prenatal treatment history, and fetal movement. They may then perform a physical examination, which can involve palpating, or pressing on, the abdomen, checking vital signs, and examining the vaginal area.

Doctors may also perform or order various tests, which can include:

A doctor may also classify placental abruption during their examination according to their findings. Classifications of the condition include:

  • Mild: There is little or no vaginal bleeding, no sign of fetal distress, and slight uterine tenderness. The pregnant person’s heart rate and blood pressure are within normal limits.
  • Moderate: There is no to a moderate amount of vaginal bleeding. There is evidence of fetal distress, significant uterine tenderness and contractions, and changes in the pregnant person’s heart rate and blood pressure. A person may also develop blood clotting changes.
  • Severe: There is no to a heavy amount of vaginal bleeding. The pregnant person is in shock and experiences sustained uterine contractions and blood clotting changes. There is a high risk to the fetus.

Placental abruption usually occurs before 37 weeks of gestation, during the third trimester of pregnancy. The condition may lead to life threatening health complications for the pregnant person and the fetus.

Complications for the pregnant person can include severe bleeding, which may lead to further complications, such as:

Complications for the fetus may include:

Placental abruption occurs when the vascular networks that connect the side of the placenta and the uterine wall are separated.

Healthcare professionals and scientists do not always know why this occurs. However, they associate several risk factors with the condition.

These include a person’s health history and behaviors, conditions that may increase the risk of placental abruption, and trauma to the abdomen.

Health history risk factors include:

  • having a history of placental abruption in previous pregnancies
  • being age 35 years or older
  • having high blood pressure
  • smoking
  • using cocaine and other recreational drugs

Conditions that may increase a person’s risk of placental abruption include:

Trauma to the abdomen that may increase a person’s risk of placental abruption includes:

  • the impact of a fall
  • a motor vehicle accident
  • a violent blow to the abdomen

Treatment for placental abruption can depend on various factors, including the severity of the abruption and how close to term a person is.

Doctors may treat a person who is less than 37 weeks pregnant and has mild placental abruption conservatively. This can involve admittance to an obstetrics unit in the hospital for close monitoring until the fetus is mature enough for delivery or the person’s condition changes.

If a person has moderate or severe placental abruption, doctors may induce vaginal delivery or perform a caesarean section.

Placental abruption may affect a person’s blood clotting ability. Vaginal delivery may therefore present a lower risk to the pregnant person, as it may result in less bleeding. However, an emergency caesarean delivery may protect the fetus if there are signs of fetal distress.

After delivery, healthcare professionals will continue to monitor the health of the pregnant person and the baby.

As healthcare professionals and researchers do not always know what causes placental abruption, a person cannot typically avoid the condition. However, they can take steps to reduce their risks, such as:

  • stopping or avoiding smoking
  • avoiding recreational drug use
  • managing other health conditions that may contribute to placental abruption
  • attending regular prenatal appointments
  • avoiding situations that may result in abdominal trauma, where possible
  • contacting healthcare professionals immediately if symptoms or abdominal traumas occur

Can smoking increase the risk of placental abruption?

Yes, smoking can increase a person’s risk of placental abruption. This may be due to the vasoconstrictive effect of smoking, which can narrow the uterine and umbilical arteries.

Can vigorous exercise cause placental abruption?

Studies have found that the risk of placental abruption is 7.8 times greater in the hour after moderate or heavy exertion than after light or no exertion.

However, the study also indicated that women who engage in moderate or heavy physical activity more than three times a week are at a lower risk. Moderate exertion is generally considered safe.

Is placental abruption more common in older mothers?

Being age 35 years or older is a risk factor for placental abruption.

The outlook for placental abruption can vary depending on several factors.

Each year, placental abruption accounts for 1% to 5% of mortalities in pregnant people and 1% to 40% of fetal mortality rates.

The risk of mortality for the pregnant person and the fetus is typically lower if the placenta partially separates from the uterine wall, and higher if it separates completely. However, without timely medical treatment, both partial and complete placental abruption are life threatening.

People who have experienced placental abruption before may be at higher risk of the condition. Recurrence occurs in 3% to 10% of pregnant people.

Seeking immediate medical care may help prevent continued bleeding and improve a person’s outlook.

Placental abruption is a serious condition that can occur during pregnancy. It occurs when the placenta prematurely detaches from the uterine wall.

This may cause symptoms like bleeding and abdominal pain, and can result in severe complications and death for the pregnant person and the fetus.

A person cannot prevent placental abruption, but can take steps to lower their risk of the condition. These include managing other health conditions and avoiding smoking and other substance use.

If a person experiences symptoms of placental abruption, they should contact a health professional, the emergency services, or go to the emergency department of a hospital. Immediate medical care may improve the outlook of the pregnant person and the fetus.

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