context: The wonderful bond you create with your baby when you breastfeed is like no other. And experts agree that breast milk is ideal for your infant. But even though you want to give your baby the best start you can, you can't help but be concerned. What will nursing do to your breasts? Think of their size and shape, for example. Throughout your life -- and especially during pregnancy and breastfeeding -- the size and shape of your breasts can change. Breast size is determined by how much fatty tissue there is. Making milk creates denser tissue in your breasts. After breastfeeding, both the fatty tissue and connective tissue in your breasts may shift. Your breasts may or may not return to their pre-breastfeeding size or shape. Some women's breasts stay large, and others shrink. But sagging or staying full can be as much a result of genetics, weight gain during pregnancy, and age as a result of breastfeeding. When you're nursing, the flow of milk can stretch your breast skin and tissue. That leaves some women with an "empty" or "stretched out" look to their breasts when the milk-producing structures shrink to the size they were before you got pregnant. It's a common cosmetic breast problem after breastfeeding, but it isn't a medical concern. Women often fear that breastfeeding will make their breasts sag. But other factors can change your breast appearance more than breastfeeding. These include: BMI -- body mass index, a measure of your percentage of body fat The number of pregnancies you've had A large pre-pregnancy breast size Age A history of smoking Each breast is independent. So what happens to one breast during breastfeeding won't necessarily happen to the other. Breast engorgement, or painful overfilling of the breasts with milk is a common condition that may leave one breast slightly misshapen afterward, for instance. Any dimpling or puckering of your breast may be a sign of a breast lump underneath and should be checked by your doctor. Breast tissue extends up toward your armpit. So, as breast tissue swells with milk and then shrinks again after breastfeeding, the contours of your bust line may change. Many women have uneven breasts before becoming pregnant as well as after breastfeeding. It's possible for one breast to return to its pre-pregnancy size while the other stays larger, droops, or flattens more. Some women end up with one breast a full cup size smaller or larger than the other after breastfeeding and simply learn to love the body that nourished their babies -- no matter what its shape. Most breast problems after breastfeeding are cosmetic changes, not real medical concerns. But it's wise to stay up to date on your regular breast screening tests to ensure your breast health. Breast self-exams are a simple way to keep tabs on your breast health and changes. Examine your breasts once a month, even while breastfeeding. It's especially important to examine your breasts in the months after you stop breastfeeding, as the shape and size of your breasts change. Report any lumps or unusual nipple discharge to your doctor. Some lumps can even extend to the armpit. Most lumps are benign, meaning they are not cancer. But they still should be checked for breast cancer. A breast exam by your doctor can evaluate whether a breast problem after breastfeeding needs medical attention. Have your doctor perform a breast exam once a year or any time you notice unusual breast changes after breastfeeding. A mammogram(breast X-ray) can diagnose a lump too small for you to feel. If you have a breast problem after breastfeeding, your doctor may advise a mammogram right away, rather than waiting for your regularly scheduled yearly or biannual mammogram. It's also safe to have a mammogram while breastfeeding if you need one. It won't affect your milk or your baby's health. Call your doctor if you have any of these breast problems: A lump in your breast A red, sore lump that may feel hot to the touch, which could be a plugged milk duct Dimpling or puckering of your breast Fever or flu symptoms, which could indicate a breast infection (called mastitis) Nipple retraction (the nipple turned inward) Painful breasts (more than the discomfort related to breastfeeding) Rash on your breast Unusual nipple discharge or a bleeding nipple A positive note: Breastfeeding lowers your risk of breast cancer. Women who have never breastfed have a slightly higher risk. When breast size or shape changes a lot after breastfeeding, some women consider cosmetic surgery. A breast lift, called a mastopexy, can be performed to help sagging and to reposition the nipple and areola (the dark circle around the nipple) higher on the breast. A thorough evaluation by a qualified cosmetic surgeon, including a complete breast health history, is advised before you consider surgery.