Breast cancer is the second most fatal cancer in women. Many of these deaths could be prevented if they had been found early enough. For this reason, physicians recommend that women examine their own breasts on a monthly basis beginning at age 20. Regularly doing so allows you to know your breasts well enough that when a change does occur, it will be more noticeable. Most lumps found in the breast end up being non-cancerous, but there's no way to know until you've consulted a physician. For this reason, any abnormality that's discovered should be looked at by a physician immediately. Breast self-exams can be done while lying down on your back, standing in front of a mirror, or in the shower. Place one hand under your head and check the breast on that side of your body with your other hand. Examine the entire area of the breast to beneath the armpit to over the shoulder. Using the tips of your finger, vary the pressure and pattern with which you feel. Physicians also recommend you look at your breast in a mirror for changes.