Objectives: To describe the epidemiological, therapeutic and prognostic aspects of pregnancy-associated breast cancer.

Patients and Method: This was a one-year prospective study from 1 January to 31 December 2020 at the Joliot Curie Institute of the Aristide le Dantec Hospital, including all patients with histologically confirmed breast cancer during pregnancy or at 1 year postpartum during the study period.

Results: Of 850 cases of breast cancer, 13 (1.5%) were associated with pregnancy, with an average age of 32 years. All our patients were diagnosed at an advanced stage, 46.2% at stage IIIB and 38% at stage IV. Invasive ductal carcinoma accounted for 92% of cases, with 84% SBRIII. They underwent primary chemotherapy with anthracyclines and taxanes and mastectomy. All pregnancies resulted in full-term delivery with an average birth weight of 3000 g, except for one case of late abortion and intrauterine growth retardation. Maternal prognosis was poor, with a 38% mortality rate.

Conclusion: Breast cancer is the most common cancer in pregnant women. This study showed that it is diagnosed at an advanced stage, resulting in a poor prognosis with a 38% mortality rate at one year follow-up.