Redefining ANC Coverage: Tracking Trends and Inequities With a Complete Contact-And-Content Index from MICS Data, Vietnam 2011, 2014, and 2021.

BACKGROUND: Vietnam has made substantial progress in maternal health, achieving high coverage of antenatal care (ANC) under the Millennium Development Goals. However, focusing solely on the number of ANC contacts may obscure whether women receive the essential services recommended during pregnancy. This study examined trends in ANC contacts and service content across sociodemographic groups and assessed whether inequalities changed over time. METHODS: We analyzed nationally representative Multiple Indicator Cluster Survey (MICS) data from 2011, 2014, and 2021 for women aged 15-49 years who had a live birth in the two years preceding the survey (N = 4,413). Outcomes included ANC coverage (≥4 and ≥8 contacts), ANC provided by skilled health personnel, ANC provided by medical doctors, receipt of four core ANC services (tetanus immunization, blood pressure measurement, blood test, and urine test), and a Complete ANC Coverage Index reflecting both service contacts and essential ANC content. Survey-weighted logistic regression models examined temporal trends and differences by wealth, residence, region, and ethnicity. RESULTS: From 2011 to 2021, all ANC indicators improved significantly (all p < 0.001). Coverage of ANC provided by skilled health personnel increased from 93.3% to 97.0%, while ANC provided by medical doctors increased from 80.6% to 95.0%. The proportion of women receiving all four core ANC services increased from 39.9% to 63.2%, and the Complete ANC Coverage Index more than doubled from 15.2% to 39.2%. Improvements were observed across all sociodemographic groups; however, substantial inequalities persisted. For the Complete ANC Coverage Index, temporal trends differed significantly across regions and places of residence (p < 0.05). Still, they were similar across wealth quintiles and ethnic groups (p > 0.05), despite persistent differences in absolute coverage. CONCLUSION: Vietnam has achieved substantial improvements in both ANC contacts and service content, yet important inequalities remain. Monitoring both service contacts and essential ANC content, using complementary measures such as the Complete ANC Coverage Index, provides a more comprehensive assessment of effective ANC coverage and may better inform policies to promote equitable maternal healthcare.