Prolactin in Men
Facing infertility can be very difficult, especially if you have not yet found an explanation as to why you are having troubles fathering a child. Fertility issues are often the result of hormonal imbalances, which cause the reproductive system to function abnormally. The hormone prolactin is generally only thought of as a factor in female infertility, but in fact, prolactin also plays a role in male fertility. If you are suffering from male infertility, you may want to investigate prolactin in order to find out if it may be affecting your reproductive capabilities.
Prolactin is a hormone that is secreted by both men and women. It is released by your pituitary gland, an organ responsible for regulating many of your body’s functions, including reproduction. The pituitary gland is a small, bean-shaped organ located in the middle of your brain. Your pituitary gland releases prolactin on a daily basis, both in the morning and throughout the night. Certain activities like sexual intercourse and exercise also cause your pituitary gland to release prolactin.
Hormones Regulating Prolactin
Prolactin is actually regulated by other hormones that your body produces. These include:
- dopamine (which blocks prolactin)
- serotonin ( which triggers prolactin release)
- thyroid-producing hormone (which also triggers prolactin)
What Does Prolactin Do?
In women, the role of prolactin is fairly clear: it is released in order to stimulate milk production during pregnancy. Prolactin causes the mammary glands in a woman’s breasts to enlarge, and upon birth, prolactin encourages the formation of milk. Unfortunately, it is unclear what role prolactin plays in men. However, it is evident that prolactin and infertility are linked.
Effects on Male Fertility
Like prolactin infertility in women, prolactin can also affect male fertility. In fact, if you have too much prolactin in your blood stream it can cause you to become infertile. High prolactin levels have an adverse affect on the function of your testicles, and can cause decreased testosterone levels or abnormal sperm. This can cause serious problems when it comes time to conceive. Normal prolactin levels in men are typically less than 15 ng/mL. Elevated prolactin may indicate a condition called hyperprolactinemia, and this could account for your fertility difficulties.
You can be diagnosed with hyperprolactinemia when you have more than 15 ng/mL of prolactin in your bloodstream. Symptoms of excess prolactin are often internal and difficult to see. Symptoms can include:
- decreased sperm count
- hypogonadism (in which your testes do not produce the right amounts of testosterone)
- decreased sex drive
If you have hyperprolactinemia, you will probably show few outward signs, making diagnosis difficult. However, some men with the condition do develop gynecomastia, a condition in which the breasts enlarge and look similar to a woman’s. This is a often a sign of high levels of prolactin.
Causes of High Prolactic Levels
Elevated prolactin levels in men are usually the result of overactive prolactin cells in the pituitary gland. These cells begin to grow into a tumor, called a prolactinoma, on your pituitary gland. Prolactinomas secrete prolactin hormone, and, as a result, can lead to extremely high levels of the hormone in your body. Prolactinomas in men are often larger than in women, mostly because the symptoms of the disorder are more difficult to recognize in men. In fact, prolactinomas can grow up to 5 cm in width and, if untreated, can leave you permanently infertile.
Symptoms of prolactinoma include:
- sexual dysfunction
- loss of sex drive
- decrease in body hair
- headaches or vision loss (as the tumor presses against the optic nerve in your brain)
Occasionally, other factors may play a role in elevating your prolactin levels. These include:
- prescription medications (like antidepressants and opiates)
- thyroid disease
Treatment for Prolactin Irregularities
If you have hyperprolactinemia that is affecting your fertility, there are treatments available to you. Speak with your health care provider about your options.
- Dopamine-producing medication: these medications can lower prolactin levels and shrink prolactinomas. They often restore fertility.
- Surgery: surgery is sometimes used to reduce the size of a prolactinoma.