Socio-economic inequalities in the effect of public policies and the COVID-19 pandemic on exclusive breastfeeding in Chile

Objective: To assess the impact of the addition of 12 maternity leave (ML) weeks (2011), a pay for per-formance (P4P) exclusive breastfeeding (EBF) promotion strategy (2015), and the COVID-19 pandemic in EBF inequalities in Chile.Study design: Interrupted time-series analyses (ITSAs).Methods: Aggregated national EBF data by municipality and month were collected from 2009 to 2020. We assess the impact of the three events in EBF inequalities using two procedures: 1. ITSA stratified by municipal SES quintiles (Q1-Q5); 2. Calculating the EBF slope index of inequality (SII).Results: The EBF prevalence was higher in lower SES municipalities before and after the three time-events. No impact in EBF inequalities was observed after the extended ML. The P4P strategy increased EBF at six months in all SES quintiles (effect size between 4% and 5%), but in a higher level in poorer municipalities (SII:-0.36% and-1.05%). During COVID-19, wealthier municipalities showed a slightly higher EBF at six months prevalence (SII: 1.44%).Conclusion: The null impact of the extended ML in EBF inequalities could be explained by a low access to ML among affiliated to the public health system (20%). The P4P strategy includes multiple interventions that seemed effective in increasing EBF across all SES quintiles, but further in lower quintiles. The re-strictions in healthcare access in poorer municipalities could explain EBF inequalities during COVID-19.(c) 2022 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.