 This study aimed to examine associations between maternal age and offspring outcomes in five low-income and middle-income countries. The findings suggest that younger maternal age is associated with lower birth weight, gestational age, child nutritional status, and schooling, while older maternal age is associated with increased risk of preterm birth and less two-year stunting and failure to complete secondary schooling. However, offspring of both younger and older mothers had higher adult fasting glucose concentrations. The study highlights the need for efforts to prevent early childbearing and suggests that extreme maternal age could be associated with disturbed offspring glucose metabolism.