Gestational breast cancer (GBC) or pregnancy-associated breast cancer was defined as breast cancer diagnosed during pregnancy and within 1 year of delivery. Breast cancer is the second commonest cancer after cervical seen in pregnancy and lactation. Nevertheless, the incidence is low and accounts for approximately 1 in 3000 of pregnancies. A delay in diagnosis is common and 70% to 89% of patients with operable primary lesions already have positive axillary lymph nodes. Breast cancer identified during pregnancy can be extremely distressing for the mother despite it has similar course of disease and prognosis seen in non-pregnant women of the same age and stage of disease. Diagnostic and treatment options should be carefully decided to prevent further harm to the mother or any potential risk to the developing fetus.