Last updated: Apr 21, 2008
Your breasts now:
Typically, in your 30s your breasts still have good elasticity and tone, says Shirley Archer, a health-and-fitness educator at the Stanford University School of Medicine and author of Busting Out. If you have kids now, youll notice changes postbaby. While your breasts get bigger during the actual pregnancy, you may, alas, permanently go down a half-cup or cup from your original size once youve given birth and/or breast-fed. (This phenomenon is called breast involution, a process where the milk-making system inside the breast shrinks because its not needed anymore.)


Your most common concern:
Breast pain. Many thirtysomethings have fibrocystic breasts, a grab bag term for tender lumpiness resulting from hormonal changes, says Holly Smedira, MD, a medical breast specialist at the Cleveland Clinic Breast Center. Although uncomfortable, the condition is benign and doesnt increase breast-cancer risk. Cutting back on caffeine may help alleviate some of the pain, as may taking evening primrose oil (1.3 grams orally twice a day), a natural form of fatty acid believed to interfere with the bodys production of prostaglandins (inflammatory compounds that trigger breast pain). For severe cases, doctors sometimes prescribe Danazol, a steroid derivative that decreases levels of the reproductive hormones FSH and LH, or tamoxifen, a breast-cancer drug that helps relieve breast pain by blocking estrogen receptors, thus preventing estrogens effect on breast tissue.

Best breast-cancer-screening strategy:
Talk to your doctor. Discuss having a baseline mammogram between the ages of 35 and 40, suggests Julia Smith, MD, director of the New York University Cancer Institute Breast Cancer Screening and Prevention Program. You should also get a yearly breast exam from your gynecologist and do monthly breast self-exams. Although the American Cancer Society (ACS) issued new guidelines for breast cancer screening in 2003, making self-exams optional, experts say theyre still a must-do. “The more you examine your breasts, the more likely you are to differentiate between normal hormone-related bumpiness and a potentially precancerous growth,” Smith says.

A woman who is at higher risk (that is, one who has a family history with one or more first-degree relatives with breast or ovarian cancer) should begin having regular annual mammograms at least 10 years earlier than the age at which her relative was diagnosed with cancer. So, if your mom found out she had cancer at age 45, you should start having mammograms done at age 35. Also, if you have a strong family history of the disease (two or more first-degree family members like a mother or grandmother), ask your doctor about receiving genetic screening to see if youre a carrier of the BRCA gene and ask about an annual MRI.

Best breast-saving move:
Wear a good exercise bra. This will help stave off future droopiness, Archer says. When you run sans bra, your breasts bounce up and down 2.6 inches for every step you take, according to a recent study done at the University of Portsmouth in England. The reassuring news: The study also found that wearing a sports bra reduces bounce by 74 percent.

“I recommend women do the bounce test when trying on exercise bras. If your breasts move when you jump up and down, youre not getting enough support,” Archer says. If one sports bra doesnt do the job for you, she adds, try wearing two.

Good news!
Your breast-cancer risk is still very low—only 5 percent of all cases occur in women younger than 40, according to the ACS. (Your risk during this decade is about 1 in 233, according to the National Cancer Institute.) One way to lower your odds even further: breast-feed. It protects older moms against the increased risk of breast cancer noted for women who have their first child after age 25, according to a recent University of Southern California study.

See: "5 ways to cut your breast cancer risk."