The discovery of the breast cancer generally occurs by chance: in fact modifications of the centre can encourage the women to consult a doctor. Sometimes, cancer is discovered with l’occasion d’examens of control. It is necessary to know early discovery increases the chances of cure. Complementary L’examen more the current is the mammography. But it n’est not always sufficient. One has then recourse to a taking away in order to carry out an examination under the microscope. In addition, the centres are very sensitive to the hormonal changes. During the first 2 weeks of the menstrual cycle, stimulation by the oestrogen causes the growth of the channels. During the 2 last weeks of the menstrual cycle, another hormone the progesterone causes the growth of the lobules what explains the congestion of the centres right before the menstruations. During the pregnancy, other hormonal changes prepare the centre for the production of milk. With the menopause, the production of oestrogen decreases and the glandular fabric is atrophied and is replaced by greasy fabric. Examine Your Breasts Every Month Beginning At Age 20 (see your doctor for self breast exam instructions). Check for: new lump (painful or not), unusual thickening of tissue, discharge from the nipples, change in the skin of nipples or breasts, or different breast size or shape than before. Have Your Doctor Examine Your Breasts Every Year Or Two Beginning At Age 30 Have A Mammogram Every Year After Age 40 .