The usual age range of acute lymphoblastic malignancies (acute lymphoblastic leukemia and advanced-stage lymphoblastic lymphoma) includes teenagers and young adults (<22 years of age) and coincides with the age of fertility. Concurrence of acute lymphoblastic malignancy with pregnancy is therefore most likely to happen during the younger childbearing ages. However, the therapeutic challenges posed by the dual diagnosis of lymphoblastic malignancy and pregnancy have not specifically been studied in the context of age, and management guidelines for pregnant young patients are lacking. Inconsistency in defining the legal decision-making rights of pregnant teenaged patients adds a further level of complexity in this age group. Management of this challenging combination in the young patient therefore entails unique ethical considerations. Here we present two illustrative cases of teenage pregnancy complicated by acute lymphoblastic malignancy, review the available literature, and offer suggestions for the therapeutic management of such cases in adolescent and young adult patients. Importantly, practical management recommendations are provided in the context of clinical ethics principles that are universally applicable, including in developing countries, where the highest incidence of adolescent pregnancies has been documented.