Prolactin

Prolactin is a hormone produced by the pituitary gland, and while it is best known for its role in stimulating milk production after childbirth, it actually has a surprisingly broad range of functions in both men and women. Prolactin is involved in immune regulation, reproductive function, and the balance of other hormones, making it a useful marker for understanding your overall hormonal health. Healthy prolactin levels are a reassuring sign that your pituitary gland, the master controller of many hormonal systems, is working as it should. Imagine the pituitary gland as a control tower at an airport, sending out signals to keep everything running on schedule. Prolactin is one of those signals, and while its most dramatic role is enabling breastfeeding, it also helps regulate the menstrual cycle in women and supports healthy reproductive function in men. Prolactin interacts closely with other hormones, particularly dopamine, which acts as a natural brake on prolactin release. When dopamine levels are adequate, prolactin stays within a healthy range; when dopamine signalling is disrupted, prolactin can rise. Elevated prolactin can sometimes affect menstrual regularity in women or libido and energy in men, so it is a valuable piece of the hormonal puzzle.

Several factors can temporarily raise your prolactin levels without there being any underlying concern. Stress is one of the most common, even the mild stress of having a blood test can cause a transient spike. Exercise, sleep, certain foods, and the timing of your blood draw can also influence your reading, which is why a morning fasting sample is often recommended. Some medications, particularly certain antidepressants, anti-nausea drugs, and antipsychotics, are well known for raising prolactin. In women, prolactin naturally rises during pregnancy and breastfeeding. If your prolactin level comes back higher or lower than expected, try not to worry, your GP may suggest a repeat test to confirm the result and can investigate further if needed, looking at it in the context of your symptoms and other hormone levels.