Prolactin
General information:
Provides information on infertility, amenorrhea (absence of menstrual cycle), menstrual cycle disorders and galactorrhea (milk-like discharge from the breast). In men, these are libido disorders, hypogonadism with gynecomastia (enlargement of the mammary glands) and galactorrhea. The secretion of prolactin in humans is uneven, it is low during the day and increases during sleep. The menstrual cycle has little effect on the prolactin level. During pregnancy, its level increases, and during the lactation period it fluctuates markedly depending on the rhythm of breastfeeding. Many physiological stimuli can cause an increase in the level of prolactin in the blood: irritation by sucking during breastfeeding, massaging the mammary gland outside the lactation process, sexual intercourse, stress, heavy physical work, etc.
The test for prolactin and macroprolactin has several features:
- Prolactin levels rise during sleep, so it is good to measure 2 hours after waking up
- values can increase after walking, physical exertion (climbing stairs), so it is good that the patients were at rest before the examination
- Stress affects prolactin, in more sensitive patients even venipuncture itself increases hormone levels
- Special attention in patients with hypothyroidism, polycystic ovary, epilepsy
- Taking medications (methyldopa, reserpine, morphine, metaclopramide, psychotropics)
- Sexual contacts immediately before the examination should be avoided
Sample required:
Venous blood in morning in fasting, after rest of 15-30 minutes