Placenta praevia Flashcards
Define placenta praevia.
Placenta praevia (PP) is defined as the placenta overlying the cervical os. It can be complete, partial, marginal, or low-lying.
What is the aetiology of placenta praevia? What are risk factors for placenta paevia?
Advanced maternal age
Multiple pregnancies
Tobacco use
Mechanism unknown. Only previous scarring can cause this alone, likely to be mix of risk factors.
Summarise the epidemiology of placenta praevia.
Occurs in 0.3% to 0.5% of pregnancies worldwide.
What are signs and symptoms of placenta praevia?
Scarred uterus
Painless PV bleeding
Previous ultrasound anomaly in first trimester
Lack of uterine tenderness
Low blood pressure and tachycardia
What investigations can be performed for placenta praevia?
Uterine ultrasound with colour flow Doppler analysis
FBC
Group and save
What is the management for placenta praevia?
Corticosteroids if <34 weeks
Increased scans
Anti-D if required
Potentially emergency C-section
What are complications associated with placenta praevia?
Anaemia
Preterm birth
Abnormally adherent placenta
Disseminated intravascular coagulation (DIC)
Intrauterine growth restriction (IUGR)
Fetal death
Sudden infant death syndrome (SIDS)
What is the prognosis for placenta praevia?
Placenta praevia seen in early gestation may migrate into a normal position as pregnancy progresses. About 85% of placentas that are praevia at about 15 to 20 weeks and about 33% that are praevia at 20 to 23 weeks will no longer be praevia at the onset of labour.
Maternal prognosis is generally good.
Fetal prognosis is generally good but may be compromised by excessive bleeding and intrauterine growth restriction.
Neonatal prognosis is dependent on the degree of prematurity along with the availability of specialist neonatal care.