The Association Between Early Antenatal Care and Intermittent Preventive Treatment of Malaria in Pregnancy in Sub-Saharan Africa: Effect Modification by Planned Pregnancy Status

BACKGROUND: Evidence of the association between early antenatal care (ANC) and receiving at least three doses of sulphadoxine–pyrimethamine (IPTp3+) during pregnancy is limited. It’s also unclear whether the association between early ANC and IPTp3+ is modified by planned pregnancy status. OBJECTIVES: Our primary aim was to assess the relationship between early ANC and IPTp3+ and to assess whether this relationship is modified by a woman’s planned pregnancy status. We also estimated IPTp3+ coverage across Sub-Saharan African countries. METHODS: Data on 77 183 mothers with a live birth in the past two years were analyzed using multiple indicator cluster surveys (MICSs) from 17 Sub-Saharan African countries conducted between 2013 and 2019. We used modified Poisson regression with a robust variance to assess the association between early ANC and IPTp3+, while adjusting for country, clustering, stratification and sample weights. Effect modification by planned pregnancy status was assessed on the additive and multiplicative scales. We used meta-analytic techniques to pool prevalent estimates of IPTp3+ across all countries. FINDINGS: IPTp3+ overall coverage was 22.1% (95% CI: 17.0%, 27.1%), and ranged from 2.9% (95% CI: 1.3%, 4.4%) in São Tomé and Príncipe to 51.7% (95% CI: 49.2%, 54.1%) in Ghana. IPTp3+ coverage was 30% higher among mothers who had early ANC compared to those who did not have early ANC [adjusted prevalence ratio (aPR): 1.30, 95% CI: 1.23,1.36]. There was evidence of effect modification on the additive [relative excess risk due to interaction (RERI): 0.08, 95% CI: 0.0002, 0.15] and multiplicative (aPR: 1.10, 95% CI: 1.01, 1.20) scales. CONCLUSIONS: IPTp3+ coverage was low across many of the countries in Sub-Saharan Africa. Women who had early ANC were more likely to receive IPTp3+. Women whose pregnancies were unplanned were less likely to receive IPTp3+, but our effect modification analysis showed that early ANC among such women can increase IPTp3+ coverage.