Objectives: Unwanted pregnancy is an important public health concern in low- and middle-income countries (LMICs). Using a pooled dataset from 48 Demographic Health Surveys conducted in Africa, Asia, Latin America and Europe (n = 494,778), we examined the effect of unwanted pregnancy on maternal and child healthcare utilization and child health outcomes in LMICs. Methods: We used logistic regression models to estimate the effect of unwanted pregnancy on antenatal care use, supervised delivery, childhood vaccination and three indicators of child health, viz. stunting (height-for-age), underweight (weight-for-age) and wasting (weight-for-height). Results: We found that mothers of children whose pregnancies had been unwanted had a lower probability of attending four or more antenatal care visits by 3.6% (95% confidence interval = 1.9–5.4%) compared to those whose pregnancy was wanted. We did not find significant impacts of unwanted pregnancy on supervised delivery, childhood vaccination uptake or child health indicators. Conclusions: Birth characteristics, household-level determinants and country-level characteristics seem to be more closely related to maternal and child healthcare utilization as well as child health outcomes than whether the pregnancy was wanted or unwanted in LMICs.