Pregnancy and breastfeeding make demands on maternal nutrient stores. The extent of depletion and the degree to which nutrient stores are replenished between pregnancies has implications for a mother's nutritional status at conception of the subsequent child and therefore that child's birth outcomes and growth. Using follow-up data collected several years after a randomized effectiveness trial conducted in rural Bangladesh and a randomized efficacy trial conducted in semiurban Ghana, we evaluated the impact of maternal supplementation with small-quantity lipid-based nutrient supplements (LNS) or multiple micronutrients (MMN) through pregnancy (the index pregnancy) and 6 months postpartum on the growth status of the next living younger sibling conceived and born after the index pregnancy. In both Bangladesh (n = 472 younger siblings) and Ghana (n = 327 younger siblings), there were no overall differences in the growth status or the prevalence of undernutrition among younger siblings whose mothers had received LNS (or MMN, Ghana only) during and after the index pregnancy compared with the younger siblings of mothers who had received iron plus folic acid (IFA) during the index pregnancy (Ghana) or during and for 3 months after the index pregnancy (Bangladesh). These findings do not indicate that preconception nutrition interventions do not improve child growth. Rather, they suggest that any benefits of maternal LNS or MMN supplementation during one pregnancy and for 6 months postpartum are unlikely to extend to the growth of her next child beyond any effects due to IFA alone.