Breast cancer is the first cancer of women in the world and in Tunisia. It is the leading cause of death in women. Breast cancer associated with pregnancy (CSAG), defined by the occurrence of cancer during pregnancy or within 12 months postpartum, is a rare entity but has been on the rise in recent years. This can be explained by the tendency to delay pregnancies, the increase in the incidence of breast cancer in young women and the increase in the incidence of breast cancer in general. We conducted a review of the literature with the aim of summarizing the epidemiological-clinical, physiopathological, therapeutic and prognostic characteristics. Radiological diagnosis is essentially based on breast ultrasound. Mammography (with abdominal protection) is not contraindicated, the extension assessment is limited to an abdomino-pelvic ultrasound and a chest X-ray (with abdominal protection). The influence of pregnancy on the prognosis of breast cancer is a controversial subject.