Birth prevalence and risk factors of neural tube defects in Ethiopia: a systematic review and meta-analysis

Objective: This study aims to estimate the prevalence of neural tube defects (NTDs) and to identify potential risk factors in the Ethiopian context.

Study design: Systematic review and meta-analysis.

Study participants: A total of 611 064 participants were included in the review obtained from 42 studies.

Methods: PubMed (Medline), Embase and Cochrane Library databases in combination with other potential sources of literature were systematically searched, whereby studies conducted between January 2010 and December 2022 were targeted in the review process. All observational studies were included and heterogeneity between studies was verified using Cochrane Q test statistics and I² test statistics. Small study effects were checked using Egger's statistical test at a 5% significance level.

Result: The pooled prevalence of all NTDs per 10 000 births in Ethiopia was 71.48 (95% CI 57.80 to 86.58). The between-study heterogeneity was high (I²= 97.49%, p<0.0001). Birth prevalence of spina bifida (33.99 per 10 000) was higher than anencephaly (23.70 per 10 000), and encephalocele (4.22 per 10 000). Unbooked antenatal care (AOR 2.26, 95% CI (1.30 to 3.94)), preconception intake of folic acid (AOR 0.41, 95% CI (0.26 to 0.66)), having chronic medical illness (AOR 2.06, 95% CI (1.42 to 2.99)), drinking alcohol (AOR 2.70, 95% CI (1.89 to 3.85)), smoking cigarette (AOR 2.49, 95% CI (1.51 to 4.11)), chewing khat (AOR 3.30, 95% CI (1.88 to 5.80)), exposure to pesticides (AOR 3.87, 95% CI (2.63 to 5.71)), maternal age ≥35 (AOR 1.90, 95% CI (1.13 to 3.25)), maternal low educational status (AOR 1.60, 95% CI (1.13 to 2.24)), residing in urban areas (AOR 0.75, 95% CI (0.58 to 0.97))and family history of NTDs (AOR 2.51, 95% CI (1.36 to 4.62)) were associated with NTD cases.

Conclusion: The prevalence of NTDs in Ethiopia is seven times as high as in other Western countries where prevention measures are put in place. Heredity, maternal and environmental factors are associated with a high prevalence of NTDs. Mandatory fortification of staple food with folic acid should be taken as a priority intervention to curb the burden of NTDs. To smoothen and overlook the pace of implementation of mass fortification, screening, and monitoring surveillance systems should be in place along with awareness-raising measures.

Prospero registration number: CRD42023413490.