Galactorrhea has a myriad of causes. The most common cause of galactorrhea in both men and women is a tumor of the pituitary gland, a small pea-shaped gland situated just below the brain that produces a hormone called prolactin. It stimulates the breast tissues to produce breast milk after child birth. Tumors in the pituitary gland can lead to an unusual production of prolactin and therefore cause a milk-like discharge from the nipples. These tumors may be less than 10 mm (microadenomas) or more than 10 mm in size (macroadenomas).
Galactorrhea can be caused by underactivity of the thyroid gland (hypothyroidism). This leads to a lower than normal levels of thyroid hormones which in turn stimulates the pituitary to produce and secrete excessive amounts of prolactin and another pituitary hormone called thyroid stimulating hormone (TSH).
A common modifiable cause of galactorrhea is the intake of certain drugs like those used for the control of blood pressure (methyldopa), birth control pills, some opioid painkillers (morphine), and drugs used in depression (phenothiazines). Some herbal supplements like fennel and fenugreek can also cause galactorrhea.
Other causative factors of galactorrhea are excessive physical stimulation of the breasts associated with sexual activity and frequent self-examinations, or persistent friction due to tight clothing. Spinal cord injury or tumors, chronic kidney diseases, and other pituitary disorders can also cause galactorrhea. Sometimes the cause may not be evident in which case it is termed idiopathic galactorrhea. Oversensitivity of the breast tissue to prolactin can cause galactorrhea with even normal levels of prolactin in the body.
Symptoms Of Galactorrhea
A milk-like or grayish discharge from one or both nipples is the main symptom in galactorrhea. The discharge usually has no blood. Women with galactorrhea may have other complaints like dryness vagina, loss of libido, or pain during intercourse. There may be infrequent or irregular menstrual cycles, or no menstruation at all (amenorrhea). These are essentially due to low levels of estrogen.Infertility in both men and women can be a consequence of galactorrhea.
In others, the pituitary tumor can press upon the adjacent structures in the brain to cause various symptoms. It can press upon the nerves of the eyes and lead to partial or complete loss of vision. Increased pressure due to the space-occupying lesion may lead to headaches. Men may have breasts that are larger than usual with a milky secretion from one or both breasts, loss of sexual desire and erectile dysfunction, and other symptoms like loss of vision and headaches.
Signs and symptoms associated with galactorrhea include:
- Persistent or intermittent milky nipple discharge
- Nipple discharge involving multiple milk ducts
- Spontaneously leaked or manually expressed nipple discharge
- One or both breasts affected
- Absent or irregular menstrual periods
- Headaches or vision problems