Inequalities in antenatal care utilization in Nigeria: an ordinal analysis aligned with WHO guidelines

Antenatal care (ANC) is a key determinant of maternal health outcomes. While the World Health Organization previously recommended a minimum of four ANC visits, current guidelines emphasize at least eight antenatal contacts. Evidence from Nigeria has largely relied on binary measures of ANC utilization, limiting assessment of progress toward the current guideline. Objective: To assess ANC utilization in Nigeria and examine sociodemographic and regional factors associated with different levels of ANC utilization using an ordinal analytical framework aligned with the former four-visit and current eight-contact WHO recommendations. This study analyzed nationally representative data from the 2024 Nigeria Demographic and Health Survey. Women aged 15–49 years with at least one live birth in the reference period were included. ANC utilization was categorized into three ordered levels: fewer than four visits, four to seven visits, and eight or more visits. Descriptive statistics and design-based chi-square tests were used to assess distributions. A generalized ordered logistic regression model was applied to examine factors associated with different levels of ANC utilization and the two cumulative utilization thresholds. Overall, 28% of women reported no antenatal care attendance during their most recent pregnancy. Among all women, 47% reported fewer than four ANC visits, 36% reported four to seven visits, and only 17% attained eight or more visits. Higher education was significantly associated with attaining at least four ANC visits (adjusted odds ratio [AOR]: 5.33; 95% CI: 4.26–6.66), while women in the richest households had substantially higher odds of achieving eight or more visits (AOR: 4.38; 95% CI: 3.34–5.74). Marked regional inequalities were observed, with women in the South West having significantly higher odds of attaining eight or more ANC visits compared with those in the North Central region (AOR: 6.91; 95% CI: 5.74–8.31). Although slightly more than half of women in Nigeria reported at least four ANC visits, fewer than one in five reported eight or more visits, with substantial socioeconomic and regional inequalities. The findings indicate that factors associated with attaining at least four visits are not always of the same magnitude as those associated with attaining eight or more visits. Policies aimed at improving ANC utilization should address socioeconomic and regional inequalities while strengthening access to and continued use of ANC services.