Even if you aren't lactating, you can experience milky discharge from your breasts, as well as other colors.
"You can have [nipple discharge] from bloody, clear or yellowish-green," OB-GYN Dr. Lisa Masterson explains. "It all needs to be checked out. Your doctor needs to evaluate it to see if it's just an infection. If it's associated with pain, it's more likely to be an infection or [an obstruction] of the duct."
Nipple discharge can also be indicative of more serious conditions like fibrocystic breasts and brain tumors. "Most of the time, it's benign, especially if [the discharge] is from both breasts," Dr. Lisa adds. "But you've got to get it checked out."