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Placental Abruption


The Manual's Editorial Staff

Last full review/revision Jun 2021| Content last modified Jun 2021
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What is the placenta?

  • The placenta is an organ that grows on the inside, upper part of your uterus (womb) when you're pregnant

  • It has many large blood vessels to carry oxygen and nutrients from you to your baby

  • The placenta's blood vessels form the umbilical cord to connect the placenta to your baby

  • About 15 minutes after you deliver your baby, the placenta comes off your uterus and goes out your vagina

  • That's why it's also called the "afterbirth"

What is placental abruption?

A placenta that starts to pull away from the uterus before delivery is called placental abruption. The placenta may pull away a little bit or a lot. The more that it pulls off, the more dangerous it is for you and your baby.

  • Placental abruption is more likely to happen after 20 weeks of pregnancy

  • If the placenta pulls away only a little bit, your baby might not grow as much or there might be too little amniotic fluid

  • If the placenta pulls away fully, your baby could die

  • To treat placental abruption, doctors will have you stay in the hospital and may deliver your baby early

Doctors usually don't know why placental abruption happens. However, it's more likely to happen if you:

  • Have uncontrolled high blood pressure

  • Use cocaine

  • Had placental abruption before

  • Have a serious injury to your abdomen (like from a car crash)

  • Smoke tobacco

Problems With the Placenta

Normally, the placenta is located in the upper part of the uterus, firmly attached to the uterine wall until after delivery of the baby. The placenta carries oxygen and nutrients from the mother to the fetus.

In placental abruption (abruptio placentae), the placenta detaches from the uterine wall prematurely, causing the uterus to bleed and reducing the fetus’s supply of oxygen and nutrients. Women who have this complication are hospitalized, and the baby may be delivered early.

In placenta previa, the placenta is located over or near the cervix, in the lower part of the uterus. Placenta previa may cause painless bleeding that suddenly begins late in pregnancy. The bleeding may become profuse. The baby is usually delivered by cesarean.

Problems With the Placenta

What are the symptoms of placental abruption?

Symptoms depend on how much the placenta has pulled away from your uterus but can include:

  • Vaginal bleeding

  • Cramps in your belly or sudden, intense belly pain

  • A dangerously low drop in blood pressure (shock)

How can doctors tell if I have placental abruption?

  • Doctors suspect placental abruption based on your symptoms

  • They’ll usually do an ultrasound to tell for sure—this test uses sound waves to create a moving picture of the insides of your uterus

  • Doctors may also do blood tests and check your baby’s heart rate

How do doctors treat placental abruption?

Doctors will have you stay in the hospital on bed rest so they can watch you. You may get medicine to help your baby’s lungs grow in case your baby has to be delivered early.

If your symptoms start to get better, doctors will let you walk around and may even let you go home.

Doctors will deliver your baby as soon as they can if:

  • You keep bleeding

  • Your baby's life is in danger

  • You’re at or more than 36 weeks along

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