Abstract Objectives Scaling-up nutrition interventions during pregnancy may provide human capital gains by lowering the risk of adverse birth outcomes associated with reduced long-term socioeconomic outcomes. We estimated gains in years of schooling and lifetime wages of scaling up prenatal maternal nutrition interventions for a 137 low- and middle-income countries. Methods Through a comprehensive review of the literature, we identified four prenatal maternal nutrition interventions with convincing-level of evidence for improving birth outcomes: prenatal multiple micronutrient supplements (MMS), calcium supplements, iron-folic acid supplements (IFA), and balanced protein energy supplements (BEP) among underweight pregnant women (BMI < 18.5 kg/m2). Effect sizes for intervention impact were derived from systematic reviews and random-effects meta-analysis. We focused on low birthweight (LBW) and preterm birth (PTB) as primary birth outcomes. We used the 2015 LBW and PTB prevalence estimates to calculate country-specific absolute reductions attributable to scaling-up a given prenatal nutrition invention. We then used an effect size based on a de novo review of the economics literature to quantify gains in schooling and lifetime wages due to reductions in LBW/PTB under two hypothetical scale-up scenarios of 50% and 90% coverage. Results For each country, returns on schooling and lifetime wages were estimated for scaling-up each prenatal nutrition intervention. For example, in Bangladesh, scaling-up IFA supplements from current coverage of 26% to 90% was estimated to reduce LBW prevalence by 3.2% contributing to a predicted increase of 0.11 million school years and US$153 million in wages per birth cohort. Similarly, scaling-up MMS, calcium supplements, and BEP to 90% coverage was predicted to increase schooling by 0.25, 0.17, and 0.07 million years, and wages by US$338, US$223, and US$97 million, respectively, per birth cohort. Global, regional, and national-level estimates for schooling and wage gains for each nutrition intervention will be presented. Conclusions Our findings indicate that scaling-up prenatal maternal nutrition interventions will contribute to substantial population-level increases in human capital, particularly in countries with a high burden of low birthweight or preterm birth. Funding Sources Bill and Melinda Gates Foundation.