Highlighting Caesarean Awareness Month: CHRISTUS Children’s to Host Placenta Accreta Spectrum Workshop for Providers

Placenta accreta is a significant obstetric condition where the placenta grows too deeply into the uterine wall. Normally, the placenta detaches from the uterus after childbirth, but in cases of placenta accreta, it remains attached, leading to severe complications, including massive blood loss after delivery. This condition is part of a spectrum known as placenta accreta spectrum, which includes placenta increta and placenta percreta, depending on the depth of placental invasion.

With placenta accreta, the placenta attaches too deeply into the uterine wall but does not penetrate the muscle. In cases of placenta increta, the placenta invades deeper, penetrating the uterine muscle. Placenta percreta is the most severe form, where the placenta penetrates through the uterine wall and can involve other organs such as the bladder. Each type presents varying levels of risk and may require different management strategies.

Cesarean Deliveries and Placenta Accreta

The relationship between cesarean deliveries and placenta accreta is noteworthy. Historically, cesarean deliveries were followed by the saying Once a cesarean, always a cesarean, but this perspective has evolved. Today, the possibility of a Vaginal Birth After Cesarean (VBAC) is encouraged under the right circumstances, especially considering that each subsequent cesarean delivery increases the risk of complications, including placenta accreta.

Following a C-section, the inside lining of the uterus gradually heals and repairs itself over time in preparation for the next pregnancy,” explained Dr. James Hill, professor and director of the Maternal-Fetal Medicine Division for the Department of Obstetrics and Gynecology at CHRISTUS Children’s. “However, previous C-sections can disturb the normal surface of the uterus and create opportunities in future pregnancies for the placenta to abnormally attach too deeply into the wall of the uterus. Normally, the placenta detaches from the inside lining of the uterus after childbirth, but in some pregnant women who have previously had a C-section before pregnancy, the placental tissue remains firmly attached to the inside lining of the uterus after childbirth, leading to potential complications such as severe bleeding.

Dr. Hill, who is also a professor with Baylor College of Medicine, added that it's not only multiple cesarean deliveries, but any uterine surgery that increases this risk due to scarring. In addition, maternal age over 35 and the presence of placenta previa—a condition in which the placenta grows in the lowest part of the uterus and covers the opening of the cervix—can be risk factors for placenta accreta. In cases of placenta accreta, women may require emergency steps to control the bleeding and prevent further complications, such as blood transfusions or a hysterectomy.

Diagnosis and Management

In Texas, obstetrical facilities are designated from Level I to Level IV. Levels III and IV facilities are equipped to handle complex cases like placenta accreta, and new rules introduced in late 2023 stress the importance of these specialized teams and facilities in managing placenta accreta spectrum cases. These guidelines emphasize early diagnoses in improving maternal and fetal outcomes, as well as early screening for women with risk factors. Management often involves planning for delivery in a high-level facility (Level III or IV), where a multidisciplinary care team is available to provide comprehensive care.

In Level IV hospitals, a dedicated placenta accreta spectrum team is on standby, Dr. Hill said. When a case is diagnosed early, this multidisciplinary team meets ahead of time to plan the delivery. In emergencies where the condition isn’t detected until delivery, the team is required to respond within 30 minutes to ensure optimal care. While Level III hospitals can manage without a specific team, they should be ready to handle such cases.

Reducing Risk Through VBACs

VBACs offer an opportunity to reduce the risks associated with multiple cesarean deliveries. While there is debate over what a safe number of cesarean deliveries may be, the consensus is that the risk increases with each procedure.

When discussing the safety of multiple C-sections, I emphasize that each subsequent surgery typically involves more complexity than the last, said Dr. Hill. While there is no definitive research indicating a safe number of cesarean sections, risks, including complications with the placenta and injury to nearby organs, increase with each procedure. If possible and safe, I advocate for women with a history of C-sections to consider vaginal delivery.

Ultimately, early diagnosis and a high-level of care is crucial for optimizing outcomes in placenta accreta spectrum cases.

I would urge expectant mothers at risk for placenta accreta to deliver at a Level III or IV maternal care facility before labor begins, as recommended by Texas designation rules, said Dr. Hill. Choosing a hospital with a dedicated multidisciplinary team is key to managing the significant risk of life-threatening bleeding post-delivery.