RESUMO
Background: Though optimal antenatal care (ANC4+) use is absolutely critical, only 43% of women had ANC4+ in Ethiopia and nearly 64% in Tigray in 2019. Furthermore, only 20% of women had their first ANC visit during their first trimester in 2016. However, there is no literature on area based disparity of ANC4+ use in Tigray. Therefore, this study is aimed to generate evidence for ANC4+ use using the Kilite-Awlaelo Health and Demographic Surveillance System (KA-HDSS) database. Methods: A population-based longitudinal study was employed on 5,414 women from 12 kebelles included in the KA-HDSS site of Tigray. A pregnancy database was used as a source of data. A Line graph was used to depict the trend of ANC4+ use. A stratified robust Poisson model was fitted to estimate the incidence rate ratio (IRR) for women from rural and urban areas separately. Results: The ANC4+ coverage was 36.3% (95% CI=35.0-37.6%) - 34.2% in rural versus 52.8% urban areas, with an increasing linear trend. Single marital status (IRR=1.29; 95% CI=1.17-1.42); able to read and write (IRR=1.15; 95% CI=1.01-1.32); primary education (IRR=1.22; 95% CI=1.11-1.34); ANC follow-up (2015-2018) (IRR=1.42; 95% CI=1.23-1.64); previous pregnancy exposure (IRR=2.20; 95% CI=1.98-2.45); and having 6+ children (IRR=1.11; 95% CI=1.01-1.21) determined ANC4+ use for rural women. Marital status (Divorced/widowed/separated) (IRR=0.79; 95% CI=0.66-0.95); primary education (IRR=1.44; 95% CI=1.16-1.79); ANC follow-up (2015-2018) (IRR=2.00; 95% CI=1.59-2.50); previous pregnancy exposure (IRR=1.54; 95% CI=1.31-1.80); and having 6+ children (IRR=1.18; 95% CI=1.07-1.31) determined the ANC4+ use for urban women. Conclusion: The optimal ANC coverage is significantly low, with significant disparity by geographical area and increasing trend. However, further efforts have to be made to maximize the optimal use of ANC, particularly for women from rural areas.