From the Guidelines
Expectant management of placenta previa involves close monitoring and conservative treatment until fetal maturity is reached, typically around 36-37 weeks gestation, with a focus on minimizing risks associated with preterm birth and sudden, severe bleeding. Here's the recommended approach:
- Hospitalize patients with symptomatic placenta previa (vaginal bleeding) for observation, as this condition presents significant risks to both maternal and fetal health through uncontrolled vaginal bleeding 1.
- Administer corticosteroids (betamethasone 12 mg IM, two doses 24 hours apart) to promote fetal lung maturity if between 24-34 weeks gestation, as this can reduce respiratory complications if preterm delivery becomes necessary.
- Provide iron supplementation (ferrous sulfate 325 mg orally daily) to prevent or treat anemia, which is a common complication of placenta previa.
- Monitor fetal well-being with regular ultrasounds and non-stress tests, as close monitoring is crucial due to the risk of sudden, severe bleeding.
- Restrict physical activity and pelvic exams to minimize bleeding risk, as digital pelvic examination should be avoided until diagnoses such as placenta previa, low-lying placenta, and vasa previa have been excluded 1.
- Administer tocolytics (e.g., nifedipine 10-20 mg orally every 4-6 hours) if preterm contractions occur, to delay delivery and allow for fetal maturation.
- Prepare for potential emergency cesarean delivery at any time, as severe bleeding can occur unexpectedly.
- Plan for cesarean delivery at 36-37 weeks if the placenta remains previa, as this is the recommended gestational age for delivery in cases of placenta previa.
The approach is justified by the fact that placenta previa can resolve as pregnancy progresses, but close monitoring is crucial due to the risk of sudden, severe bleeding 1. Transabdominal US and transvaginal US are essential for diagnosing and monitoring placenta previa, as they can accurately diagnose the condition and guide management 1. By following this approach, healthcare providers can minimize risks associated with preterm birth and sudden, severe bleeding, and improve outcomes for both mothers and babies. The key to successful management of placenta previa is close monitoring and a multidisciplinary approach to care, with a focus on minimizing risks and optimizing outcomes.
From the Research
Expectant Management of Placenta Previa
The expectant management of placenta previa involves several key components, including:
- Avoidance of digital vaginal examination 2
- Delay of delivery until 36 weeks' gestation and/or documented fetal lung maturity 2, 3
- Transfusion support to maintain maternal hematocrit greater than or equal to 30% 2
- Serial ultrasonography to assess fetal growth and placental location 4, 5
- Antepartum fetal heart rate monitoring 2
- Glucocorticoids to promote fetal lung maturity 5, 2
- Tocolytic therapy to stop preterm labor 4, 2, 6
- Elective delivery by cesarean section, especially if the placenta overlaps the internal os 4, 2, 6
Timing of Delivery
The optimal timing of delivery for women with stable placenta previa is between 36 and 37 weeks' gestation, balancing the risks of maternal hemorrhage and neonatal morbidity 3.
Inpatient vs. Outpatient Management
For selected patients, outpatient management of symptomatic placenta previa may be an acceptable alternative to traditional inpatient management, with significant cost savings 5.
- Outpatient management involves weekly corticosteroids, ultrasonographic evaluations, and readmission for recurrent bleeding 5
- Inpatient management involves bed rest, minimal ambulation, and close monitoring 5
Special Considerations
- Placenta accreta is a common complication in patients with prior cesarean sections and placenta previa, requiring careful management and planning 2, 6
- The use of blood-saving techniques, such as cell saver, may be beneficial in cases of anticipated major bleeding 6
- A multidisciplinary team approach is recommended for the management of placental abnormalities 6