Norm of prolactin in women: the effect of increased hormone on the body

With the help of prolactin, breasts form and grow (the hormone is also responsible for the development of ducts), and milk is produced after the baby is born. In addition, ovulation depends on prolactin. The hormone is involved in the regulation of progesterone production: its increase leads to a decrease in progesterone production and, as a result, to a slowdown in ovulation processes.

During pregnancy, prolactin levels increase significantly. This is a normal process. After childbirth, during lactation, it remains high (although compared to pregnancy, of course, it falls). This explains the very low chance of pregnancy during breastfeeding. But still, if the cycle is restored, breastfeeding cannot be considered a reliable method of contraception.

Outside of pregnancy, prolactin levels fluctuate depending on the day of the menstrual cycle. A strong and sustained increase that is not associated with bearing or feeding a child has a negative effect on the body. This condition is called hyperprolactinemia.

The importance of prolactin for the female body

The role of prolactin in the female body is quite significant. This hormone is involved in such important processes as:

• formation and growth of the breast, development of its ducts;
• ovulation;
• regulation of progesterone production (high prolactin levels reduce progesterone production and slow down the ovulation process);
• normalization of lactation after the birth of a child.

The participation of the hormone in the mentioned processes explains the increase in its indicators during gestation and during breastfeeding. During lactation, hormone levels become lower than during pregnancy, but still remain elevated. During these periods, the probability of conception is zero. But when the menstrual cycle is restored, breastfeeding loses its role as one of the methods of contraception.

A sustained increase in the hormone, not associated with pregnancy and breastfeeding, has a negative effect on a woman’s body and is called hyperprolactinemia.

Prolactin and the ability to have children

In some cases, high prolactin levels can lead to infertility. Prolactinoma tumors affect the pituitary gland, and it reduces the production of hormones. This condition is known as hypopituitarism. In men, it causes decreased libido and hair loss. In women, this can lead to infertility.

Hyperprolactinemia complicates pregnancy and disrupts the normal production of the hormones estrogen and progesterone. This causes the ovaries to either release eggs irregularly or stop producing eggs completely.

Medicines and other treatments for prolactinoma restore fertility in most women.

Normal indicators

In the absence of pregnancy, fluctuations in prolactin values ​​depend on the beginning and end of the menstrual cycle. The norm values ​​are shown in the table:

For pregnant and lactating women, the normal prolactin level is much higher. An increase in values ​​is observed from the first trimester, and in the third trimester the hormone concentration reaches 318 units or more. This level is not a cause for alarm; it does not indicate pathology.

Treatment and observation for drug-induced hyperprolactinemia

Treatment and observation
If the disease is asymptomatic, drug treatment with dopamine agonists is not recommended. If a patient develops signs of prolonged hypogonadism - decreased bone density, other characteristic symptoms, replacement therapy with estrogen or testosterone is recommended.

It is recommended to begin treatment of symptomatic hyperprolactinemia by stopping medications that affect prolactin levels. If this is not possible, the medications used should be replaced with others that have a similar effect but do not cause hyperprolactinemia.

Expert opinion on dopamine agonist therapy in such patients remains controversial, although these drugs are reported to reduce prolactin levels in 75% of patients, but clinical trials have shown that their use can lead to exacerbation of psychotic states.

Signs of elevated prolactin

Periodic exceeding of permissible limits is observed not only in pregnant women. But such manifestations do not always indicate health problems. However, the appearance of the following symptoms of increased prolactin is a cause for concern:

• menstrual irregularities or complete cessation;
• decreased visual acuity;
• the appearance of discharge from the mammary glands;
• coarsening and increase in the size of the mammary glands;
• decreased libido;
• weight gain due to the usual diet and normal physical activity;
• malaise accompanied by headache.

Such symptoms do not always indicate hyperprolactinemia. But its manifestation becomes a reason to visit a gynecologist-endocrinologist.

Drug treatment

Symptomatic hyperprolactinemia due to any cause is treated with oral dopamine agonists, cabergoline, bromocriptine, quinagolide, and pergolide. Treatment begins with low doses of the drug, which are gradually increased to therapeutic doses.

Consistent adherence to the treatment plan allows a very rapid reduction in clinical symptoms to be observed, with regression of vision-related symptoms in the first days and restoration of sexual function within 2-3 weeks.

If hyperprolactinemia is caused by an adenoma, a repeat MRI scan may show improvement as early as 6 weeks after starting treatment.

Currently, the first-line dopamine agonist is cabergoline due to its greater efficacy and lower likelihood of side effects compared with bromocriptine. This difference in effectiveness may be explained by the fact that cabergoline is more specific for dopamine receptors in lactotrope cells.

Dopamine agonists have the side effects of nausea, postural hypotension, and impulsive behavior. Long-term use of high doses of cabergoline has been shown to be associated with valvular fibrosis, so periodic cardiac ultrasound examination is recommended.

Reasons for exceeding normal values

If elevated prolactin is detected in women, the causes and consequences may be different. Among the main reasons, the following factors are noted that provoke excessive production of the hormone:

• the formation of benign neoplasms – adenomas or prolactinomas;
• polycystic ovary syndrome;
• pathological processes in the liver and kidneys;
• adrenal dysfunction;
• pathological changes in the functioning of the brain.

Prolactin increases due to stress. Exceeding the norm is also possible due to taking certain medications.

Possible consequences

Sustained elevated levels of prolactin, not associated with pregnancy and lactation, indicate the possible development of hyperprolactinemia or other pathological changes. Among them:

• dysfunction of reproductive organs;
• menstrual irregularities;
• impossibility of maturation and decreased activity of eggs;

• weakening of the production of follicle-stimulating hormones.

Against the background of the mentioned disorders, the likelihood of infertility increases. In addition, excessive production of the hormone often becomes a prerequisite for a sharp deterioration in vision and memory, sleep disturbance and emotional state.

Hyperprolactinemia caused by pituitary adenomas

Pituitary adenomas that secrete prolactin develop from lactotropic cells. Tumors of this type make up up to 50% of all pituitary tumors and can be characterized by increased secretion of not only prolactin, but also other adenocorticotropic growth hormones and thyroid-stimulating hormones.

Prolactinomas are classified by size into microprolactinomas and macroprolactinomas. Microprolactinomas are more common in women than in men (20:1). Macroprolactinomas have the same ratio.

The spread of macroprolactinomas in men is explained by the fact that men have a longer asymptomatic period, so the adenoma is already advanced when diagnosed. Most prolactinomas are not cancerous, but in rare cases these tumors can metastasize.

Diagnostic measures

It is impossible to determine the hormone level by the presence/absence of the symptoms mentioned above. For this purpose, a venous blood test is performed. The procedure is scheduled for the morning. No special preparation is required for collecting material, but it is advisable to calm down before visiting the laboratory.

Blood tests are carried out 3 times at different stages of the menstrual cycle. If elevated prolactin levels are confirmed in non-pregnant women, the patient is prescribed mammography and MRI of the brain.

Diagnosis of hyperprolactinemia

It is impossible to determine elevated prolactin based on symptoms. The only way to detect excessive hormone production is a blood test. The sample is taken from a vein in the morning. The patient is advised to be in a calm state of mind at this time.

The analysis is done three times, because it is necessary to establish the level of prolactin in different phases of the cycle. In addition to studying the hormonal profile, additional tests are used in diagnosis. If hyperprolactinemia is confirmed, a gynecologist-endocrinologist may refer for mammography or magnetic resonance imaging of the brain.

How to prepare for a prolactin test

Preparing for the study:

• We recommend donating blood between 8 and 11 am;
• blood must be donated on an empty stomach, after an 8-12 hour overnight fast;
• on the eve of the study - a light dinner with limited intake of fatty foods;
• on the day of the test, you can drink still water and it is better to avoid coffee and tea;
• 24 hours before the test, exclude alcoholic beverages;
• 1 hour before the test it is better to refrain from smoking;
• 24 hours before the study, exclude the use of medications (in consultation with the attending physician);
• 24 hours before the test, eliminate emotional and physical stress;
• You should not donate blood after radiography, ultrasound, massage, endoscopic and physiotherapeutic procedures;
• It is recommended to rest for 10-20 minutes before donating blood.

Prevention

There are no special preventive measures for this disease. The risk of developing hyperprolactinemia can only be reduced by avoiding serious physical activity and psycho-emotional stress.

Women who have been diagnosed with hyperprolactinemia should consider other methods of contraception. If desired, you can continue to use oral contraceptives, but estrogen-containing drugs should be replaced with agents whose action is based on pure gestagens or prolonged gestagens. Also, in case of hyperprolactinemia, the advisability of surgical sterilization should be considered. It is not recommended to use intrauterine devices: they provoke irritation of endometrial receptors, which can cause increased secretion of prolactin.

Treatment of patients with high prolactin

There is no need to treat elevated levels if:

• hormone concentration up to 1000 U/l;
• the structure of the pituitary gland is not changed;
• the functioning of the organs of the reproductive system occurs without changes;
• the person is of normal weight.

The main assistant in the fight against increased prolactin is dopamine. They “compete” with each other, creating balance. To normalize the condition, it is recommended to do what brings pleasure and give the body time to rest. The following have a positive effect on hormonal levels:

• bananas,
• apples,
• watermelons,
• strawberry,
• prunes.

A good relaxing effect is massage, which allows you to normalize your emotional state.
Regular physical activity can reduce stress hormone levels. They should not be debilitating, as this may become a prerequisite for its increase. The best option is to perform gymnastics in a well-ventilated area or outdoors.

Before bed, you can make and take soothing infusions that contain mint, lemon balm and hops. Tablets with valerian extract also reduce anxiety levels. When using twigs, give preference to a tincture made from seeds. For this purpose 40 gr. raw materials are poured with alcohol or vodka in an amount of 230 grams, infused for two weeks in a dark place. The tincture is taken in a large spoon, diluted in 60 ml. water 30 minutes before meals.

During drug treatment, different therapeutic techniques are used for women and men. They are contacted only if other methods cannot reduce the hormone level.

Is it possible to prevent hormonal imbalance during stress?

The main rule is to listen to your body. With hormonal changes due to stress, unreasonable palpitations and anxiety appear. Sleep ceases to give a feeling of rest. In the morning there is fatigue, fog in the head, muscle pain. There is a decrease in sexual desire and a disruption in eating behavior.

You need to give time for rest and relaxation. Try to spend more time outdoors. Don’t forget about communication, which helps reduce anxiety and switch to positive experiences.

Thus, prolactin is more of a female stress hormone, since its increase is more often observed in the fairer sex. An increase in certain substances in the body is a protective effect. But if the condition is not corrected, physiological problems appear. Therefore, it is important to monitor your emotional state.

References

• Huang W., Molitch M.E. Evaluation and treatment of galactorrhea. 2012
• Melmed S. et al. Diagnosis and treatment of hyperprolactinemia: Endocrine Society Clinical Practice Guidelines, 2011.
• D. Kasper. Harrison's Principles of Internal Medicine. NY. 2015.
• Kazanueva F.F. and others. Guidelines of the Pituitary Society for the diagnosis and treatment of prolactinomas. 2006;
• Melmed S., Kleinberg D. Anterior lobe of the pituitary gland. Williams Textbook of Endocrinology. 2008.
• Mancini T., Casanueva F.F., Giustina A. Hyperprolactinemia and prolactinomas. 2008.
• Losa M. Surgical treatment of prolactin-secreting pituitary adenomas: initial results and long-term results. 2002.
• Cavallaro R, Cabergoline treatment of risperidone-induced hyperprolactinemia: a pilot study. 2004.