Lactation and Galactorrhea
Lactation is the production of milk from the mammary glands. Normally, female breasts undergo various changes during pregnancy, in order to get ready for breastfeeding when the baby is born. However, in some cases the production of milk can occur with no relation to pregnancy. The lactation process unrelated to pregnancy is known as galactorrhea.
Breast Milk Secretion Causes
Galactorrhea occurs due to high levels of Prolactin. Prolactin is the hormone produced by the pituitary gland, which initiates lactation. In low levels, prolactin can’t stimulate the production of milk from the mammary glands. However, when this hormone reaches its critical levels in the blood it affects the function of the mammary glands, by enlarging them and starting to produce milk components. These milk components are later released through the excretory ducts.
During breastfeeding the production of milk is stimulated by local mechanisms like nipple stimulation and frequent and regular emptying of the mammary ducts.
Galactorrhea is not a disease, but it can be a sign of something more serious. It usually occurs in women, even those who have never had children or after menopause. Various health conditions can lead to breast milky discharge. However, in some cases the real cause can’t be determined and the condition may resolve on its own.
Causes of Breast Discharge Without Pregnancy
- Prolactinoma – a benign type of tumor that affects the pituitary gland. It is one of the most common causes of hyperprolactinemia
- Head trauma – as the pituitary gland is settles in an osseous space on the skull base, it can be easily damaged during head trauma
- Medications – like antidepressants, antipsychotics, calcium channel blockers, H2 antagonists, etc.
- Liver diseases like liver cirrhosis may increase the levels of prolactin due to poor elimination,
- Chronic kidney disease also leads to high levels of prolactin due to poor elimination of prolactin through the urine
- Cocaine or opioid use
- Birth control pills
- Damage to the nerves of the chest wall from chest trauma, surgery of the chest or burns
- Excessive breast stimulation, which may be associated with sexual activity, frequent breast self-exams with nipple manipulation (see also: nipple pain), etc.
Other Signs of Galactorrhea
Other signs and symptoms that can accompany galactorrhea include:
- Persistent or intermittent milky nipple discharge that has no trace of blood
- 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
How Is Galactorrhea Diagnosed
Finding the real cause of galactorrhea is often very difficult and requires a lot of tests and examinations. Some of these examinations include:
- Physical examination – during with your doctor will gently press and squeeze the area around your nipple in order to see some of the fluid. A total bimanual examination of the breasts is performed by your doctor in order to find any suspicious areas of the breast tissue.
- Analysis of fluid discharged from the nipple
- Blood test, to determine the level of prolactin in the bloodstream. If the levels of prolactin is elevated, the levels of TSH (thyroid stimulating hormone) should be checked.
- Pregnancy test, in order to check if pregnancy is the cause. Pregnancy should be ruled out first as one of the possible causes of nipple discharge.
- Mammography and ultrasound of the breast tissue
- Magnetic resonance imaging (MRI) to check for a tumor or other abnormality of your pituitary gland, if your blood test reveals elevated prolactin levels.