What is placenta accreta? It's a rare condition that affects around 0.2% of pregnancies. Normally, your placenta forms an attachment to the uterine lining, called the endometrium. But if you have placenta accreta, it goes even further and attaches to your uterine wall.
What Is the Placenta?
The placenta is a tissue that connects you and your baby, acting as a bridge. It provides your growing baby with blood, oxygen, and nutrients and removes waste products. Normally, the tissue detaches from the endometrium after you’ve given birth and comes out in the afterbirth.
Placenta Accreta Types
Placenta accreta falls within a spectrum of three closely related conditions, each defined by how your placenta attaches to the uterus.
The three types of placental attachment are:
Placenta accreta
This is the most common and mildest form of placental attachment. In this, the placenta attaches to the uterine wall but doesn’t affect any of the muscles of the uterus.
Placenta increta
This is an intermediate form of attachment where the placenta grows more deeply into the uterine muscle. In cases of placenta increta, the placenta doesn’t pass through the uterine wall, but it does attach to the muscles of the uterus. About 15% of people who experience placental attachments will have this type.
Placenta percreta
This is the most severe form of attachment, where the placenta grows beyond the uterus and may attach to nearby organs, such as your bladder or intestines. It is the least common type of placental attachment, accounting for 5% of cases.
Placenta Accreta Causes
Cases of placenta accreta are on the rise. In the 1960s, it affected only about 1 in 30,000 pregnancies, but by 2016, the rate increased to an estimated 1 in every 272 pregnancies.
The main reason for this increase is higher rates of C-sections. This procedure can scar your uterus, making it harder for the placenta to attach properly in later pregnancies.
Jennifer Gilner, MD, director of the Placenta Accreta Spectrum and Complex Obstetric Surgery Care Program at Duke University, says the main factor connecting C-sections to placenta accreta spectrum is where the embryo implants and develops.
“If the implantation of a future embryo happens in or near the scar on the uterus, it can attach to scar tissue or muscle instead of the specialized lining of the uterus,” she says. She adds that because scar tissue doesn’t stretch like uterine muscle, it can cause complications during pregnancy.
Placenta accreta risk factors
With each C-section you’ve had, your chances of experiencing placenta accreta go up slightly. After one C-section, your risk is 0.3%, but that number rises to 6.7% if you’ve had five or more.
Gilner explains that having a low-lying placenta, combined with a history of C-sections, is closely linked to placenta accreta spectrum. “Likely the uterus is just weaker down there, so the risk of disrupting an old scar increases with each C-section,” she says.
Other procedures that cause scarring on or near your uterus may also raise your chances of having placenta accreta. Examples of these surgeries include:
- Myomectomy. A surgery that removes noncancerous tissue in the uterus, called uterine fibroids.
- Hysteroscopic surgery. A procedure that allows a surgeon to see inside your uterus using a thin, flexible tube that is inserted through the vagina.
- Uterine embolization. A procedure that shrinks uterine fibroids by cutting off their blood supply. This is done through an injection.
- Pelvic irradiation. Radiotherapy used to destroy cancer cells.
- Endometrial ablation. A procedure that uses heat or cold to destroy the tissue lining your uterus. This is usually done to treat heavy menstrual bleeding.
- Other uterine surgery
Other factors that may make you more likely to have placenta accreta include:
- Being over the age of 35
- Having placenta previa, a condition where your placenta partially or completely blocks your cervix. This is seen in 80% of placenta accreta cases.
- Previous childbirth. The more children you’ve had, the more likely you are to develop this condition.
- Having Asherman syndrome, a condition where scar tissue forms in your uterus, mainly from uterine surgeries.
Placenta Accreta Diagnosis
Placenta accreta is usually diagnosed with an ultrasound. This can happen during a routine appointment. Your doctor may also specifically check for the condition if you fall into a high-risk category. In some cases, an MRI scan may be done to find out whether you have placenta accreta, increta, or percreta.
Ideally, your medical team will know how deeply your placenta is attached so they can decide on the best plan for your delivery. However, it can be challenging to see the full extent of the attachment with imaging, so it isn’t always possible to get a complete picture.
“Some of the subtle phonographic findings may be more evident once the uterus and uterine wall have stretched out,” says Gilner. This usually happens around 27 to 29 weeks into pregnancy. She explains that in lower-grade placenta accreta cases, these signs are still hard to detect, which is why 40%-50% are diagnosed during delivery.
Placenta accreta ultrasound
During an ultrasound, a technician will use an electronic wand to see your reproductive organs. The wand sends sound waves through your abdomen or vagina. These waves bounce off the structures inside your body to create their images.
During the ultrasound, you’ll lie on an examination chair, usually in a dark room so the technician can see the screen more easily. They will apply a water-soluble gel to your skin, which helps transmit sound waves, and run the wand over your skin. The entire procedure usually takes less than 30 minutes, and it shouldn’t be uncomfortable.
Placenta Accreta Symptoms
You likely won’t have any symptoms of placenta accreta. In cases of more severe attachment (such as placenta percreta), you might feel pain in your pelvic area or see blood in your urine.
Placenta Accreta Complications
The biggest problem caused by placenta accreta occurs during delivery. If you have placenta accreta, your placenta won’t detach like it's supposed to and come out in the afterbirth. This can cause problems for both you and your baby.
Complications for your baby include:
- The need for an early delivery, three to six weeks before the due date, depending on the severity of the accreta and whether you also have previa
- An increased risk of needing the newborn intensive care unit (NICU) due to premature birth
- Instability from heavy bleeding, which could result in an even more premature and possibly unplanned delivery
The main complications from this condition are those that you'll face yourself. They include:
- Hemorrhaging. Extremely heavy bleeding that can be life-threatening if not properly treated.
- The need for a hysterectomy. This may be the only way to remove your placenta.
Placenta Accreta Treatment
The exact treatment for your condition will depend on how firmly your placenta is attached. You should plan on having your baby in a hospital. This will allow your medical team to provide any emergency medical treatment that you or your baby might need — particularly emergency blood transfusions if you start to lose too much blood. Your doctors may have you meet with different medical team members before delivery, like a hematologist to make sure you aren't anemic. Your doctors may also suggest you get antenatal steroids to help mature your baby’s lungs before delivery since your delivery will be planned earlier than your due date.
In most cases, you’ll need to have a combination C-section and hysterectomy — called a Cesarean hysterectomy. This removes your entire uterus along with your placenta. Afterward, you won’t be able to have more children.
Gilner notes that being diagnosed with placenta accreta may change how you plan to give birth, so it's important to ask your medical team plenty of questions before it’s time to have your baby. "Ask the hospital about the methods they use to prioritize and maintain early mother-baby contact, how they support lactation if that's the birthing person's choice, and how they help recognize that it was still a birth — even if it turned into a surgical emergency."
A hysterectomy removes your uterus, and in some cases, your ovaries too. In cases of placenta accreta, your ovaries will be left in place to prevent premature menopause.
If you want to have more children, your doctor might try to only remove parts of your placenta, leaving some of it attached to your uterus. There’s a chance that your placenta will dissolve and be reabsorbed into your body over time.
But if you don’t heal properly, you’ll still need to have a hysterectomy later. You’ll also run the risk of infection from the remaining parts of your placenta.
The most dangerous scenario would be having a vaginal birth without realizing that you have placenta accreta. In this case, you’d need immediate emergency attention to deal with the life-threatening amounts of blood that you may lose. Your medical team will need to act quickly to find the best treatment method.
Placenta Accreta Recovery
Recovering from placenta accreta after delivery might be different from a standard delivery. If you had blood transfusions or a hysterectomy, you may need to stay in the intensive care unit (ICU) for a day or two to recover from extreme blood loss.
Your total hospital stay will likely be between three and five days — which is typical for a C-section. During this time, you’ll receive pain medication. Your doctor will likely also give you a prescription to help manage pain at home. If your delivery was particularly difficult, your doctor will schedule regular checkups to monitor your recovery and your baby’s health. Gilner stresses the importance of staying in touch with your surgical team after delivery because complications can still happen after surgery.
Since each pregnancy is different, make sure that you and your doctor decide on a birth and treatment plan that feels right for you. Gilner recommends transferring your delivery to a hospital with a dedicated accreta center for more serious forms of placenta accreta spectrum. “That’s where we know the outcomes are best.”
Placenta accreta survival rate
Placenta accreta can lead to severe bleeding after childbirth (postpartum hemorrhaging), which can be life-threatening. However, the survival rate is generally high, at around 93%. In some cases, a hysterectomy (removal of the uterus) is necessary to prevent further complications.
Takeaways
Placenta accreta, a pregnancy condition where the placenta attaches too deeply to the uterus, is becoming more common. This is largely due to the increasing number of C-sections. Other surgeries that cause uterine scarring can also play a role. Early diagnosis through ultrasound or MRI can help your doctors prepare for a safer delivery. If you have any concerns, talk to your doctor about creating a plan for your pregnancy and birth.
Placenta Accreta FAQs
What is the biggest risk with placenta accreta?
In rare cases, placenta accreta can cause severe vaginal bleeding, which can be life-threatening.
How do you fix placenta accreta?
Placenta accreta can’t be reversed, but it can be managed. Depending on your condition, your doctor may recommend bed rest, schedule a C-section to ensure a safer delivery, and, in some cases, do a hysterectomy after you give birth to lower your chances of severe bleeding.
What does placenta accreta feel like?
Most people with placenta accreta don’t have any symptoms, but it is possible to have some pelvic pain from the placenta pressing on your organs.
How common is placenta accreta after a C-section?
Placenta accreta becomes more common with each C-section. The rate of placenta accreta is 0.3% in women with one C-section, while it increases to 6.7% for those with five or more C-sections.
