Durant la grossesse, la glande mammaire subit des transformations importantes et encore mal connues. Les limites de l'examen clinique et des explorations radiologiques induisent des difficultés diagnostiques. Le cancer associé à la grossesse est rare, mais il est trop souvent découvert tardivement. Certaines lésions bénignes sont spécifiques à la gestation et l'allaitement notamment l'adénome lactant et la galactocèle.

Normal physiologic changes in the breast related to pregnancy and lactation reduce the sensitivity of physical examination and imaging modalities such as mammography. Pregnancy-associated masses are usually discovered by patient self-examination, and the clinician should proceed to ultrasonography and fine-needle aspiration/biopsy, rather than mammography. Management of a new mass in pregnancy should maximize diagnostic accuracy and minimize chances of missing breast carcinoma, although malignancy is relatively uncommon. Some benign lesions are specific during this period such as lactating adenoma and galactocele.