Comparison of Wealth-Related Inequality in Tetanus Vaccination Coverage before and during Pregnancy: A Cross-Sectional Analysis of 72 Low- and Middle-Income Countries

Abstract

Immunization of pregnant women against tetanus is a key strategy for reducing tetanus morbidity and mortality while also achieving the goal of maternal and neonatal tetanus elimination. Despite substantial progress in improving newborn protection from tetanus at birth through maternal immunization, umbilical cord practices and sterilized and safe deliveries, inequitable gaps in protection remain. Notably, an infant's tetanus protection at birth is comprised of immunization received by the mother during and before the pregnancy (e.g., through childhood vaccination, booster doses, mass vaccination campaigns, or during prior pregnancies). In this work, we examine wealth-related inequalities in maternal tetanus toxoid containing vaccination coverage before pregnancy, during pregnancy, and at birth for 72 low- and middle-income countries with a recent Demographic and Health Survey or Multiple Indicator Cluster Survey (between 2013 and 2022). We summarize coverage levels and absolute and relative inequalities at each time point; compare the relative contributions of inequalities before and during pregnancy to inequalities at birth; and examine associations between inequalities and coverage levels. We present the findings for countries individually and on aggregate, by World Bank country income grouping, as well as by maternal and neonatal tetanus elimination status, finding that most of the inequality in tetanus immunization coverage at birth is introduced during pregnancy. Inequalities in coverage during pregnancy are most pronounced in low- and lower-middle-income countries, and even more so in countries which have not achieved maternal and neonatal tetanus elimination. These findings suggest that pregnancy is a key time of opportunity for equity-oriented interventions to improve maternal tetanus immunization coverage.

Keywords: health disparities; health inequality; immunization; maternal and neonatal tetanus; vaccination.

Figure 1

National maternal tetanus immunization coverage at birth among first births; most recent DHS or MICS estimates 2013–2022 for 72 included study countries.

Figure 2

Maternal tetanus immunization coverage by country income grouping, weighted mean coverage level.

Figure 3

Maternal tetanus immunization coverage by wealth quintile, weighted mean, overall, and by country income grouping.

Figure 4

Distribution of countries’ absolute inequality in tetanus immunization coverage before pregnancy, during pregnancy, and at birth; overall and by country income grouping.

Figure 5

Absolute inequality (SII) in maternal tetanus immunization coverage by wealth quintile, before versus during pregnancy.

Figure 6

Change in absolute inequality in tetanus immunization coverage before pregnancy versus at birth.

Figure 7

Absolute inequality in maternal tetanus immunization coverage and average coverage level, before pregnancy and at birth. (Dot represents coverage level and SII in tetanus immunization coverage before pregnancy; arrowhead represents coverage and SII at birth).

Figure 8

Absolute inequality in maternal tetanus immunization coverage and average coverage level, before pregnancy and at birth, by country income grouping. (Dot represents coverage level and SII in tetanus immunization coverage before pregnancy; arrowhead represents coverage and SII at birth).

Figure 9

Inequality in maternal tetanus immunization coverage and average coverage level, before pregnancy and at birth, by whether countries had or had not achieved MNTE at time of survey. (Dot represents coverage level and SII in tetanus immunization coverage before pregnancy; arrowhead represents coverage and SII at birth).

Figure 10

Distribution of countries’ absolute inequality in tetanus immunization coverage before pregnancy, during pregnancy, and at birth; by recency of data collection.