The transition to parenthood marks a significant developmental period for the mother. Clinical and preclinical studies evidence neural and hormonal changes that support maternal behavior that is critical to infant survival and development. These changes suggest marked plasticity as a result of reproduction in the mother. Furthermore, multiple reproductive experiences may contribute to long-lasting changes to support more efficient and competent caregiving with subsequent pregnancies and births. However, less is known about neural, hormonal, and behavioral changes that occur as a function of parity--the number of children a woman has. Here, we highlight behavioral, neural, and hormonal changes that occur as women transition to parenthood, with a special emphasis on parity-related changes. Limitations and directions for future research are discussed, as well as clinical implications to be considered in light of parity research.