A diagnosis of breast cancer during pregnancy or the postpartum period is an unfortunate occurrence. Hormonal factors appear to play an important role early on in the development of breast cancer; however, pregnancy itself does not clearly influence the outcome of an established breast cancer. Diagnosis can be challenging in a pregnant woman and delays in diagnosis are common. Treatment decisions must take into consideration not only toxicity to the mother, but short- and long-term consequences for the fetus as well. Other special considerations with pregnancy-associated breast cancer include the timing of delivery, the potential for nursing, and concerns for future fertility. In general, management of pregnancy associated breast cancer follows the same principals as in non-pregnant patients of similar age. With thoughtful application of available therapies, outcome can be optimized for both the mother and her child.