Most of the breast lesions found during pregnancy are benign. Pregnancy associated breast cancer (PABC) is defined as cancer that occurs during pregnancy or within 1 year of delivery. Aim of the study: To diagnose breast lesions during pregnancy, detect incidenceof masses as well as the incidence and early diagnosis of PABC. Patients and methods: 500 pregnant women (190 primigravida, 254 mutigravidaand 56 lactating) attending Kasr Al Ainy outpatient clinic having breast complaints were included in the study. Ultrasound was performed for all patients. Further investigations were performed when indicated (Mammography, MRI or core biopsy). Results: Incidence of breast mass was 25.6%. Within those cases, 5.46 had PABC. The overall incidence of PABC was 1.4%. Biopsy was performed in 13 patients (9 pregnant and 4lactating). We diagnosed 7 malignant masses (4 lactating and 3 pregnant). Pathology revealed5 invasive duct carcinoma, 1 inflammatory carcinoma and 1 adenocarcinoma. Positive family historywas found in 85.7% of malignant cases. Conclusion: Most breast masses were benign. The overall incidence of PABC was 1.4% and 5.46% within patients diagnosed with a breast mass. Obstetricians should be aware of the importance of breast examination when there is a breast complaint during pregnancy.