Association between preterm birth and cigarette smoking among pregnant women in Africa: Systematic review and...

Smoking during pregnancy is an important predictor for birth outcomes that have an impact on their postpartum health, cognitive abilities, and economic standing. While extensive research has been conducted on the association between smoking and preterm birth, there is a scarcity of comprehensive evidence specific to the Africa region. This review aimed at generating summarized evidence on the association between maternal exposure to cigarettes smoking and preterm birth in Africa.

PubMed, Google Scholar, and the African Journals Online databases were used to conduct a thorough literature search. Review inclusion was open to all designs of observational studies. The Newcastle-Ottawa Scale (NOS), which was used for case-control, cohort and cross-sectional studies, was the measure used for quality assessment. To get the pooled estimates and the associated 95% confidence interval (CI), the random-effects model was utilized.

A total of four studies were included in the prevalence and association meta-analysis. Among women with active smoking exposure, the pooled prevalence of preterm birth was 19.44% (95% CI [16.04, 22.84]), with moderate heterogeneity (I ² = 63.49%, p = .05). Among passive the prevalence was 17.5% ([10.88, 24.12]) with no observed heterogeneity (I ² = 0%). The overall pooled prevalence was 19.22% ([16.28, 22.16]). For association estimates, the overall pooled AOR across studies was 3.18 ([1.30, 5.06]).

This review showed that maternal tobacco exposure, whether active or passive, is associated with an increased risk of preterm birth in African countries.