Effect of the enhancing nutrition and antenatal infection treatment (ENAT) intervention on birth weight in Ethiopia: a cluster randomized controlled trial

Background: The Enhancing Nutrition and Antenatal Infection Treatment (ENAT) intervention was implemented in Ethiopia to improve newborn birth weight (BW) by strengthening the contents and quality of antenatal care (ANC), especially point-of-care testing for maternal infections. This study examined the effect of the ENAT intervention on birth weight. Methods: We conducted a cluster randomized controlled trial of 22 clusters (health centers), randomized equally between 11 intervention and 11 control clusters. This study enrolled and followed pregnant women from ANC booking to the end of pregnancy or loss to follow-up. The primary outcome was mean BW, and the incidence of low birth weight (LBW) was the secondary outcome. We presented univariate comparisons of outcomes between the intervention and control arms for mean BW and LBW. Multilevel analyses using random effects models were performed to adjust for clustering and individual-level covariates. Results: We enrolled and followed up 4,868 and 4,821 pregnant women in the intervention and control arms, respectively, from March 2021-July 2022. During follow-up, 3445 pregnant women in the intervention and 3192 in the control delivered in the health centers, and BW measurements of their babies were recorded within 48 h. The mean BW was 3,152 g (standard deviation (SD) = 339.8 g) in the intervention and 3,044 g (SD = 353.8 g) in the control arms (mean difference, 108 g; 95% confidence interval (CI): 91.3-124.6; P = 0.000). Adjusting for clustering and several covariates, the mean BW remained significantly higher in the intervention arm than in the control arm (adjusted ß coef., 114.3; p = 0.011). The incidence of LBW was 4.7% and 7.3% in the intervention and control arms, respectively. The adjusted risk of LBW was significantly lower by 36% in the intervention arm than in the control arm (adjusted relative risk, 0.645; p = 0.027). Conclusion: This study provided sufficient evidence of the effectiveness of the ENAT intervention in improving birth weight in the study population. The intervention demonstrated that an increase in birth weight can be attained by availing point-of-care testing, strengthening infection prevention, and maternal nutrition within the ANC platform of public health facilities in a low-income setting. Trial Registration: Registered at Pan African Clinical Trial Registry (PACTR) database dated 09/05/2023, https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=25493 . The unique identification number for the registry is PACTR202305694761480.