Disease Description (Causes and Symptoms)
- Definition: A condition in which the chorionic villi of the placenta become abnormally deeply attached to the myometrium because the spongy decidua, which normally allows the placenta to detach, is absent or insufficient (placenta accreta spectrum; includes conditions ranging from mild accreta to increta and percreta).
- Pathophysiology: The chorionic villi can penetrate areas where the endometrium–basal layer (spongy decidua) is absent or damaged and adhere to the myometrium (accreta), invade into the myometrium (increta), or extend beyond the uterine wall into other organs (percreta).
- Major causes and risk factors: Previous cesarean section (scar), endometrial damage from previous uterine curettage or similar procedures, placenta previa, multiple births, and a history of uterine surgery.
- Main symptoms: Failure of the placenta to detach properly after delivery; severe vaginal bleeding immediately after delivery or later (possibly accompanied by abdominal pain); persistent bleeding, pus, or foul-smelling lochia due to retained placental tissue.
Treatment Methods
- General principles: Controlling bleeding and protecting the mother's life are the top priorities. If suspected before delivery, planned delivery at a large medical facility with blood transfusion preparations and a multidisciplinary team is recommended.
- Management at delivery
- Conservative procedures: Manual removal of the placenta from inside the uterus is not recommended because of the risk of bleeding. Small retained fragments may be removed through a procedure.
- Bleeding control: Uterine massage, uterotonic agents (such as oxytocin), consideration of uterine artery embolization, and blood transfusion (with preparation for massive transfusion).
- Surgical treatment: In cases of extensive adherence or uncontrollable bleeding, immediate hysterectomy after cesarean section is often necessary. If uterine preservation is attempted, a multidisciplinary approach, including vessel ligation and local resection, is required.
- Medications: Uterotonic agents (oxytocin) for bleeding, adjunctive medications to control bleeding (such as tranexamic acid), and antibiotics for infection prevention or treatment may be used. Methotrexate has been used in some cases to manage retained placenta conservatively, but evidence is limited and caution is required.
- Hospitalization and management: Intensive care nursing, repeated tests (CBC and coagulation tests), and preparation of obstetrics, anesthesia, interventional vascular, and transfusion teams.
- Lifestyle management and precautions: Visit a hospital immediately if persistent bleeding, high fever, foul-smelling lochia, or severe lower abdominal pain occurs after delivery. If prenatal risk factors such as a previous cesarean section are present, delivery should be planned at a high-level medical institution.
Checklist Before an Outpatient Visit (Including Sample Questions)
- Recommended items to bring
- Records of previous obstetric history (number of cesarean sections and history of uterine surgery)
- Recent ultrasound and MRI images and reports, if available
- List of current medications, including anticoagulants, and allergy information
- Records of recent bleeding patterns and the timing and characteristics of pain (amount, color, and odor of bleeding, etc.)
- Recent test results (CBC, blood type and crossmatch, etc.) or test request forms
- Information to organize before the outpatient visit
- Dates and hospital names of previous surgeries and whether surgical complications occurred
- The status of placental separation and treatment history during previous deliveries
- Sample questions
- "According to the recent ultrasound findings, where is the placenta located, and how likely is invasion?"
- "What recommendations do you have regarding the delivery plan (timing and method)?"
General Sample Questions to Ask the Doctor
- What are the main side effects and risks of this medication (or treatment)?
- What is the prognosis, including the risk of bleeding and risks in future pregnancies?
- What preparations are needed in case a blood transfusion or emergency surgery becomes necessary?
- What will the delivery method (such as an early cesarean section) and expected length of hospitalization be?
Examples of Disease-Specific Questions
- I have previously had a cesarean section. How should the delivery plan be made to reduce the risk of placenta accreta?
- Placenta accreta is suspected on ultrasound. In what situations is MRI necessary, and how accurate is MRI for diagnosis?
(Note: Placenta accreta can cause serious complications during delivery, including severe bleeding and hysterectomy. Therefore, if risk factors are present or the condition is suspected, multidisciplinary planning and preparation for blood transfusion before delivery are essential.)