Neonatal Risks in Placenta Previa
The primary risk to the newborn in placenta previa is prematurity and its associated complications, as approximately 67% of these infants are delivered preterm, with perinatal mortality currently at 4-8% primarily related to complications of prematurity. 1
Primary Neonatal Risks
Prematurity-Related Complications
- Preterm delivery occurs in approximately 67% of placenta previa cases, making prematurity the dominant neonatal risk 1, 2
- Planned cesarean delivery is recommended at 34 0/7 to 35 6/7 weeks of gestation for uncomplicated placenta previa, which inherently exposes the newborn to late preterm complications 3, 4
- Earlier delivery may be required for persistent bleeding, preeclampsia, labor, rupture of membranes, or fetal compromise, further increasing prematurity risks 3
- Antenatal corticosteroids should be administered when delivery is anticipated before 37 0/7 weeks to reduce neonatal respiratory complications 3, 4
Perinatal Mortality
- Current perinatal mortality with placenta previa is 4-8%, primarily driven by complications of prematurity rather than direct hemorrhagic complications 1
- This represents a dramatic improvement from historical outcomes due to advances in prenatal ultrasound, cesarean delivery, and transfusion medicine 5
Secondary Neonatal Risks
Complications from Maternal Hemorrhage
- Antenatal bleeding, preterm labor, and preterm prelabor rupture of membranes are associated with both maternal and neonatal morbidity 6
- Massive maternal hemorrhage requiring transfusion occurs frequently, which can compromise uteroplacental perfusion and fetal oxygenation 4
- Approximately 50% of women with placenta accreta spectrum beyond 36 weeks require emergent delivery for hemorrhage, which increases risk of fetal compromise 3, 4
Risks from Associated Conditions
- When placenta previa is diagnosed, assessment for placenta accreta spectrum and vasa previa is essential, as vasa previa carries risk of fetal exsanguination when membranes rupture 7
- Women with placenta previa and prior cesarean deliveries have dramatically increased risk of placenta accreta spectrum (3% with no prior cesarean, up to 67% with five or more cesareans), which increases surgical complexity and duration of delivery 6
Optimizing Neonatal Outcomes
Delivery Planning to Minimize Neonatal Risk
- Delivery must occur at a level III or IV maternal care facility with neonatology expertise immediately available 6, 3, 4
- Preoperative coordination with neonatology is essential to prepare for potential resuscitation of a preterm infant 3, 4
- The timing of delivery at 34 0/7 to 35 6/7 weeks balances neonatal complications against increased maternal bleeding risk after 36 weeks 3, 4