Socioeconomic inequalities in birth outcomes: An 11-year analysis in Colombia

To examine socioeconomic inequalities in birth outcomes among infants born between 2008 and 2018 and assessed trends in inequalities during that period in Colombia, a middle-income country with high levels of inequality emerging from a long internal armed conflict.

Using birth certificate data in Colombia, we analysed the outcomes of low birth weight, an Apgar score <7 at 5 minutes after birth and the number of prenatal visits among full-term pregnancies. Maternal education and health insurance schemes were used as socioeconomic position (SEP) indicators. Inequalities were estimated using the prevalence/mean of the outcomes across categories of the SEP indicators and calculating the relative and slope indices of inequality (RII and SII, respectively).

Among the 5,433,265 full-term singleton births analysed, there was a slight improvement in the outcomes analysed over the study period (lower low-birth-weight and Apgar<7 prevalence rates and higher number of prenatal visits). We observed a general pattern of social gradients and significant relative (RII) and absolute (SII) inequalities for all outcomes across both SEP indicators. RII and SII estimates with their corresponding CIs revealed a general picture of no significant changes in inequalities over time, with some particular, time-dependent exceptions. When comparing the initial and final years of our study period, inequalities in low birth weight related to maternal education increased while those in Apgar score <7 decreased. Relative inequalities across health insurance schemes increased for the two birth outcomes but decreased for the number of prenatal visits.

The lack of a consistent improvement in the magnitude of inequalities in birth outcomes over an 11-year period is a worrying issue because it could aggravate the cycle of inequality, given the influence of birth outcomes on health, social and economic outcomes throughout the life course. The findings of our analysis emphasize the importance of policies aimed at providing access to quality education and providing a health care system with universal coverage and high levels of integration.