Antenatal care attendance and risk of low birthweight in Burkina Faso: a cross-sectional study

BACKGROUND: Low birthweight is a major contributor to infant mortality. We evaluated the association between antenatal care (ANC) attendance and low birthweight among newborns in 5 regions of Burkina Faso. METHODS: We utilized data from the baseline assessment of a randomized controlled trial evaluating azithromycin distribution during the neonatal period for prevention of infant mortality. Neonates were eligible for the trial if the weighed at least 2500 g at enrollment and were 8–27 days of age. Data on ANC attendance and birthweight was extracted from each child’s carnet de santé, a government-issued health card on which pregnancy and birth-related data are recorded. We used linear and logistic regression models adjusting for potentially confounding variables to evaluate the relationship between ANC attendance (as total number of visits and ≥ 4 antenatal care visits) and birthweight (continuously and categorized into < 2500 g versus ≥2500 g). RESULTS: Data from 21,223 births were included in the analysis. The median number of ANC visits was 4 (interquartile range 3 to 5) and 69% of mothers attended at least 4 visits. Mean birthweight was 2998 g (standard deviation 423) and 8.1% of infants were low birthweight (< 2500 g). Birthweight was 63 g (95% CI 46 to 81 g, P < 0.001) higher in newborns born to mothers who had attended ≥4 ANC visits versus < 4 visits. The odds of low birthweight among infants born to mothers with ≥4 ANC visits was 0.71 (95% CI 0.63 to 0.79, P < 0.001) times the odds of low birthweight among infants born to mothers who attended < 4 ANC visits. CONCLUSIONS: We observed a statistically significant association between ANC attendance and birthweight, although absolute differences were small. Improving access to ANC for all women may help improve birth outcomes. TRIAL REGISTRATION: The parent trial is registered at clinicaltrials.gov: NCT03682653; first registered 24 September 2018. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12884-021-04310-6.