Background Infections are one of the most common causes of neonatal mortality, and maternal colonization has been associated with neonatal infection. Data on carriage of bacterial pathogens and mother-child transmission patterns in low- and middle-income countries is sparse. Methods We sought to quantify carriage prevalence of extended-spectrum-beta-lactamase (ESBL) -producing and carbapenem-resistant Enterobacterales (CRE) among pregnant women and their neonates and to characterize risk factors for carriage in a rural area of Amhara, Ethiopia. We sampled 211 pregnant women in their third trimester and/or labor/delivery and 159 of their neonates in the first week of life. Results We found that carriage of ESBL-producing organisms was fairly common (women: 22.3%, 95% CI: 16.8-28.5; neonates: 24.5%, 95% CI: 18.1-32.0), while carriage of CRE (women: 0.9%, 95% CI: 0.1-3.4; neonates: 2.5%, 95% CI: 0.7-6.3) was rare. Neonates whose mothers tested positive for ESBL-producing organisms were nearly twice as likely to also test positive for ESBL-producing organisms (38.7% vs. 21.1%, p-value: 0.06). Carriage of ESBL-producing organisms was also associated with woreda (district) of sample collection (Fisher exact test maternal p-value: <0.01; neonatal p-value: <0.01) and recent antibiotic use (maternal p-value: 0.55; neonatal p-value: 0.011). Conclusions Understanding carriage patterns of potential pathogens and antibiotic susceptibility among pregnant women and newborns in this region will help to inform local, data-driven recommendations to prevent and treat neonatal infections.

The authors have declared no competing interest.

This work was supported by the Bill & Melinda Gates Foundation [INV-010382 to G.C.].

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Ethics Review Board (IRB) of Saint Pauls Hospital Millennium Medical college (Addis Ababa Ethiopia) gave ethical approval for this work [PM23/274] Boston Childrens Hospital (Boston United States) gave ethical approval for this work [IRB-P00028224] Harvard T.H. Chan School of Public Health (Boston United states) gave ethical approval for this work [IRB19-0991]

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