Investigating Spatial Patterns and Determinants of Optimal Antenatal Care Attendance Among Pregnant Women in Nigeria

The World Health Organization in a bid to improve mother and child experience during pregnancy and delivery had recommended for optimal birth experience, at least four antenatal visits (ANC4+) in 2002 and recently an upward review to eight minimum antenatal visits (ANC8+) in 2016 to a health facility by pregnant women. This study therefore is to investigate the implications of these optimal recommendations with respect to spatial effects and determinants in Nigeria using data extracted from the 2018 Nigerian Demographic Health Survey. Bayesian models with appropriate priors were fitted for each of these distributions using structured additive regression modeling technique. The Integrated Nested Laplace Approximation method was used to estimate the parameters of the models. A north–south dichotomy in the spatial distribution of ANC utilization in Nigeria was prominent only at the ANC8+ utilization level. Furthermore, some interesting revelations showed that Igbo and Yoruba women in southern Nigeria shared association with attaining four antenatal visits during pregnancy, while only Igbo women had high potential for eight antenatal visits. Only Adamawa state was significantly highly associated with the two optimal ANC levels (ANC4+ and ANC8+) in the Northern region. The nonlinear effects of respondents’ current age at birth at the time of survey showed the older women have higher potential to attain higher utilization levels than the younger ones.