Live birth (viviparity) has arisen repeatedly and independently among animals. We sequenced the genome and transcriptome of the viviparous Pacific beetle-mimic cockroach and performed comparative analyses with two other viviparous insect lineages, tsetse flies and aphids, to unravel the basis underlying the transition to viviparity in insects. We identified pathways undergoing adaptive evolution for insects, involved in uro-genital remodeling, tracheal system, heart development, and nutrient metabolism. Transcriptomic analysis in the cockroach and tsetse viviparity reveals that uterine remodeling and nutrient production are increased and the immune response is altered during pregnancy, facilitating structural and physiological changes to accommodate and nourish the progeny. These patterns of convergent evolution of viviparity among insects, together with similar adaptive mechanisms identified among vertebrates, highlight that the transition to viviparity requires changes in uro-genital remodeling, enhanced tracheal and heart development (corresponding to angiogenesis in vertebrates), nutrient metabolism, and shifted immunity in all animal systems.