Ultrasound screening for vasa previa: a systematic review and meta-analysis

Area of Science:

• Perinatal medicine
• Diagnostic imaging
• Obstetrics

Background:

• Vasa previa (VP) is a rare but serious obstetric condition.
• Prenatal detection of VP is crucial for improving perinatal outcomes.
• Standardized ultrasound screening protocols may enhance VP detection rates.

Purpose of the Study:

• To evaluate the prenatal detection rate of vasa previa (VP).
• To assess perinatal survival in pregnancies screened with standardized second-trimester ultrasound protocols and third-trimester confirmation.
• To determine the diagnostic accuracy of these standardized protocols.

Main Methods:

• Systematic review and meta-analysis of cohort studies.
• Searched multiple databases (PubMed/MEDLINE, Web of Science, EMBASE, etc.) up to February 2024.
• Assessed sensitivity, specificity, and perinatal survival using fixed-effects models; risk of bias evaluated with QUADAS-2.

Main Results:

• Included 19 studies with 779,845 pregnancies; 505 VP cases identified (1 in 1,544).
• Prenatal diagnosis achieved in 97.8% of cases.
• Pooled sensitivity and specificity for standardized screening were 1.00 (95% CI: 0.99-1.00 and 1.00-1.00, respectively); pooled perinatal survival was 98.15% (95% CI: 88.30%-100.00%).

Conclusions:

• Standardized second and third-trimester ultrasound screening protocols for vasa previa are highly effective.
• These protocols achieve high detection rates with minimal false positives/negatives.
• The findings support the widespread implementation of standardized VP screening protocols.