Objective To assess the impact of the addition of 12 maternity leave (ML) weeks (2011), a pay for performance (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 restrictions in healthcare access in poorer municipalities could explain EBF inequalities during COVID-19.
The multiple benefits of exclusive breastfeeding (EBF), for children and their mothers, are well established.1e4
Kawachi describes health inequalities (HI) as ‘measurable unequal distribution, or differences, on a health outcome across individuals or defined population groups’. 5
HI could be linked to cultural, ethnic, historical, socio-economic, regional, geographical, and educational factors, among others.6,7 These inequalities have also been observed in EBF prevalence, between and within countries.8,9
Several countries have introduced successful policies to increase EBF prevalence, such as the Baby-friendly Hospital Initiative; specialised training for health professionals; counselling for mothers and their families; regulation of formula milk sales and marketing; and paid maternity leave (ML).1,2,10 However, only a few of these interventions have documented a decrease in EBF inequalities.6,11,12 Some studies have reported that ML could be successful in increasing EBF; however, this policy might present inequalities according to socio-economic status (SES).13,14
In the past decade, Chile implemented two policies that directly and indirectly promoted EBF (see Supplemental Table 1): the addition of 12 weeks of ML in October 2011, bringing the total to 24 weeks (five and a half months) and a Pay for Performance (P4P) strategy (usually defined as financial incentives or rewards for healthcare workers), in January 2015.15,16 The P4P strategy was designed to improve healthcare goals accomplishment in public healthcare centres (PHCC).17,18 In addition, the COVID-19 pandemic revealed deep inequalities in access to healthcare services, increasing household duties in women's and a rise in female unemployment. All these factors could have affected EBF practices.19
Our findings highlight that no EBF inequalities were identified after the implementation of the extended ML, which could be explained by low ML access in public health system-affiliated and the insufficient duration of the ML. Our results also suggest that the P4P is successful in increasing EBF across all socio-economic quintiles, but in a higher level in lower SES municipalities. The COVID-19 pandemic increased EBF at six months in wealthier municipalities, which had lower EBF to begin with.
Our study showed that it is imperative to reinforce EBF support across SES. Increasing the ML current duration, providing more flexible ML access and enhance EBF promotion policies, are more likely to thrive in higher EBF prevalence across SES. Follow-up studies of the EBF trend during the COVID-19 period are required.