Placental abruption is when the placenta, responsible for nourishing the baby throughout pregnancy, detaches from the uterine wall before delivery. Possible symptoms can include bleeding abdominal pain and abdominal tenderness, especially during the third trimester. Placental abruption can take away oxygen and nutrients from the baby and in some cases, early delivery is required.

Overview

What is placental abruption? 

Placental abruption, also called abruptio placentae, is the early separation of the placenta from the uterus before delivery.

The placenta is a temporary organ that connects the growing baby to the uterus during pregnancy and is essential for the efficient delivery of nutrients and oxygen from the mother to the baby, as well as waste removal from the baby’s blood. In this relatively rare pregnancy complication, the placenta may completely or partially detach, decreasing the amount of oxygen and nutrients to the foetus and causing vaginal bleeding, contractions of the uterus and abdominal pain in the expectant mother. Placental abruption necessitates immediate medical attention and treatment.^1,2

Explore the complexities of placental abruption in this informative article. Uncover the causes, symptoms, and varying degrees of this condition, and gain insights into diagnosis and treatment. Learn about risk factors, prevention measures, and when to seek immediate medical attention. Whether you are an expectant parent or interested in maternal health, this piece provides essential knowledge to help guide you.

What are the different types of placental abruption?

A partial placental abruption occurs when part of the placenta detaches from the uterine wall.

A complete or total placental abruption occurs when the placenta fully separates from the uterus. This kind is often linked to increased vaginal bleeding.

Revealed placental abruptions often present with noticeable, moderate to severe vaginal bleeding.

Concealed placental abruptions show minimal or no apparent vaginal bleeding. Blood becomes trapped between the placenta and the uterine wall. 

How prevalent is placental abruption?

Placental abruption affects about 0.6%–1.2% of pregnancies, with lower occurrences in Nordic countries and higher in a few Asian countries.^3,4

What other complications can affect the placenta?

Additional complications that can affect the placenta during pregnancy or childbirth include:

• placenta praevia and low-lying placenta
• retained placenta – when part of the placenta remains in the uterus after giving birth

What is the difference between placental abruption and placenta praevia?

In some women, the placenta attaches lower in the uterus and may cover part of or all of the cervix (the neck of the uterus). In most cases, the problem is corrected on its own as the pregnancy progresses. For some women, however, the placenta continues to lie in the lower part of the uterus as the pregnancy advances.

This condition is referred to as low-lying placenta when the placenta is less than 20 mm from the cervix, or as placenta praevia if the placenta completely covers the cervix. When the placenta detaches from the uterus, it is referred to as placental abruption. Vaginal bleeding during pregnancy and labour can be caused by both conditions. 

How does placental abruption affect mother and baby?

The condition can be life-threatening to the baby's mother. Complications include:

In the mother:

• Postpartum haemorrhage
• Need for blood transfusion
• Hysterectomy due to severe blood loss
• Blood clot risk (venous thromboembolism)
• Sepsis
• Kidney failure
• Death

In the baby:

• Low birth weight
• Asphyxia
• Brain injury caused by lack of oxygen
• Premature birth
• Severe respiratory disorder
• Stillbirth
• Perinatal death^1,4,5

Symptoms and causes

What causes placental abruption is often unknown. Possible causes include trauma or injury to the abdomen — from a fall or an auto accident — or a rapid loss of the amniotic fluid, which surrounds and protects the baby in the amniotic sac inside the uterus. 

What are the risk factors?

It is not well understood what causes placental abruption, but factors that increase the risk include:

• injury to the abdominal area
• smoking
• marijuana use
• cocaine use
• chronic high blood pressure
• pre-existing or gestational diabetes
• pre-eclampsia
• placental abruption in a previous pregnancy
• caesarean section in a previous pregnancy
• uterus abnormality
• mental stress or depression^1,3,5

What are the symptoms of placental abruption?

Each person can manifest different symptoms of placental abruption. Nevertheless, the primary indicator often involves bleeding accompanied by cramping, which is most likely to happen in the third trimester of pregnancy, especially in the last few weeks before birth. Symptoms of placental abruption may involve vaginal bleeding, however, there might not be any:

• Abdominal pain
• Back pain
• Uterine tenderness
• Uterine contractions that are longer and more intense than average labour contractions, often coming one right after another
• Decreased foetal movement

Pain in the abdomen and back often starts suddenly. The amount of vaginal bleeding may differ substantially and does not indicate how much of the placenta has detached from the uterus. In cases where blood is trapped between the placenta and uterus, there might be no visible bleeding, even when the placental abruption is severe.

These symptoms may appear similar to other conditions associated with pregnancy. Always consult with your doctor for a proper diagnosis.

Does always placental abruption result in bleeding?

In cases of concealed placental abruption, where blood collects behind the placenta, there is no evidence of vaginal bleeding.²

In other instances, the abruption develops slowly, causing occasional, light bleeding.

Pregnant women should always talk to their healthcare provider about any vaginal bleeding they experience during pregnancy.

Diagnosis and treatment

How do healthcare professionals diagnose placental abruption?

Placental abruption is diagnosed through physical examination and monitoring. Depending on the severity, you might be admitted to the hospital or advised to rest at home. Your healthcare provider will:

• Ask about the extent of the bleeding
• Ask how intense the pain is and where it is located
• Ask when symptoms started
• Monitor your blood pressure
• Monitor the foetus’s heart rate and movement
• Monitor your contractions
• Use ultrasound to identify the search of bleeding and to assess the foetus
• Recommend blood or urine tests

There are commonly three grades of placental abruption a healthcare provider will diagnose:

• Grade 1: Minimal bleeding, occasional uterine contractions, and no indications of stress to you or the foetus
• Grade 2: Mild to moderate bleeding, occasional uterine contractions, and indications of foetal stress
• Grade 3: Moderate to severe bleeding or concealed bleeding, uterine contractions that do not relax, abdominal pain, low blood pressure, and foetal death

It's crucial to communicate any symptoms or changes in symptoms with your healthcare provider.

What treatment options exist for placental abruption?

Once the placenta has detached from the wall of the uterus, it cannot be reconnected or repaired. If your placental abruption is small, your provider may advise bed rest to address your bleeding. After a few days, most women can return to their usual activities in most cases.

In the case of a moderate separation, you'll probably have to remain hospitalised. This allows for the heart rate of your baby to be monitored. Your condition will also be monitored in case a blood transfusion is required.

If your baby shows any indications of distress, your provider may induce your labour early. If vaginal birth is not possible, you will need a c-section.

Severe placental abruption is an emergency. You will need to deliver promptly, usually through a c-section. While it is very uncommon, severe abruption can, in rare instances, lead to a stillborn baby.

Prevention

Can placental abruption be prevented?

You can't prevent placental abruption, but you can reduce certain risk factors. Refrain from smoking or using illegal drugs, such as cocaine. If you have high blood pressure, it is essential to work with your healthcare provider to monitor the condition.

Make sure you wear your seatbelt every time you're in a vehicle. If you've had abdominal trauma — from a fall, an auto accident or other injury — seek immediate medical help.

If you've had a placental abruption in the past, consult with your healthcare provider before planning another pregnancy to explore ways to minimize any potential risks. 

When to see a doctor

Seek emergency care immediately if you have signs or symptoms of placental abruption such as bleeding, pelvic pain or cramping during your pregnancy, especially in the third trimester.

Summary

Placental abruption, a separation of the placenta from the uterus before birth, poses grave risks to both mother and baby. Symptoms like bleeding, abdominal pain, and reduced foetal movement are common indicators. Risk factors, including trauma, smoking, and hypertension, heighten the likelihood.

Diagnosis involves physical exams, monitoring, and ultrasound, while treatment varies from rest to emergency delivery, depending on severity. As prevention isn't always feasible, avoiding risk factors and seeking immediate medical attention for symptoms are crucial.