Searched "abnormal breast leakage" via Google - first result is as follows:
Normal vs. Abnormal
As a general rule of thumb, the only time when fluid should be leaking from a breast is during pregnancy and breast-feeding. When it happens any other time, it is best to get the breast or breasts examined by a physician just to be sure that there isn't some underlying health problem that needs to be addressed.
Leakage from Both Breasts
If fluid is leaking from both breasts, chances are good that a hidden condition is affecting the whole body in a systemic way. This may be an endocrine problem. Another possibility is that some sort of medication could be the culprit. Many different kinds of your garden-variety prescription drugs, including Prozac and birth control pills, are known to mess with the breasts. When both breasts leak, it might be a good idea to pay attention to any other symptoms that may seem unrelated, as they may all be caused by the same thing.
Leakage from One Breast
When the fluid comes from just one breast, it is much more likely that the cause is localized to just that breast. Discharge from the nipple may be a sign of any one of numerous problems ranging from breast trauma to cancer.
Get it checked out!
No matter what the case, it is very important to have these symptoms checked out by a doctor so that any potential illness or condition can be treated quickly and effectively. The doctor will ask questions about medications you are taking, other symptoms that go along with the various hormonal disruptions, and recent experiences. She will also examine both breasts and look at the color and consistency of the discharge. Tests will be ordered, if indicated by the in-office evaluation. These might include blood tests, lab tests of the discharge, or even a mammogram.