Background Congenital heart disease (CHD) is the most common major birth defect, yet reported global birth prevalence remains highly variable. A robust, contemporary estimate is essential for public health planning and pediatric service allocation. Objective To systematically estimate the global birth prevalence of CHD among children aged 0–6 years and assess how methodological factors—particularly study setting and diagnostic criteria—influence reported rates. Methods We conducted a systematic review and meta-analysis of observational studies on CHD birth prevalence, including 22 studies with 23,333,048 participants. Eligible studies involved children aged 0–6 years with CHD defined by ICD-10 Q20–Q28 or equivalent criteria. A sample size–weighted median prevalence was calculated, and meta-regression was used to evaluate the contribution of methodological factors to between-study variability. Results The overall sample size–weighted median birth prevalence of CHD was 6.7 per 1000 live births. Methodological variation was substantial: • Hospital-based studies reported a weighted median of 13.1 per 1000, about 1.9-fold higher than the 7.0 per 1000 in population-based studies. • Echocardiography-based detection yielded 1.6-fold more cases than clinical examination. Meta-regression identified sample size as the strongest predictor of reported prevalence (p < 0.001), explaining 34% of the heterogeneity (I² = 100%). Conclusion Globally, CHD birth prevalence is about 6.7 per 1000 live births, though hospital-based sampling and echocardiography inflate estimates. Recognizing these methodological effects is essential when interpreting surveillance data and planning pediatric cardiology resources. Persistent data gaps in Africa and Europe highlight the urgency of establishing standardized CHD surveillance systems.

Dr. Hadeer Abdeltwab is a pediatrician who has full MRCPCH and four years of structured paediatric training through the Egyptian Fellowship Programme. She is actively involved in research with special interest in Pediatric cardiology research. She is currently participating in 3 systematic reviews and meta-analyses preparing for publication.