How terrible is hyperprolactinemia during pregnancy?

Prolactin is a polypeptide hormone, also called prolactin, which is one of the hormones secreted by the pituitary gland. Women secrete prolactin vigorously in the late pregnancy and lactation period to promote breast development and lactation. The highest level of prolactin in the serum of non-pregnant women generally does not exceed 20 ng/ml. The secretion of prolactin is pulsatile and varies greatly throughout the day. The pulse amplitude of prolactin secretion increases rapidly within 1 hour of sleep, and then the secretion level is maintained at a high level during sleep, and begins to decline after waking up. The serum prolactin secretion concentration at 3 or 4 o'clock in the morning is twice that of noon.

The secretion of prolactin is affected by many factors. In addition, drugs such as progesterone, dexamethasone, adrenal cortisol, and acute stress such as strenuous physical activity and trauma can cause increased secretion of prolactin.

Some drugs can also cause an increase in prolactin. Taking drugs such as reserpine, chlorpromazine, and morphine for a long period of time can inhibit the release of prolactin inhibitory factors by changing the production, absorption, and metabolism of dopamine, resulting in excessive prolactin secretion and amenorrhea and galactorrhea. Oral contraceptives can cause an increase in prolactin secreted by the pituitary gland and a decrease in gonadotropin, leading to amenorrhea and galactorrhea. This is why some people who take oral contraceptives cannot get pregnant immediately.

Some other reasons can also lead to increased prolactin, such as primary hypothyroidism, idiopathic amenorrhea, galactorrhea syndrome, primary hyperthyroidism, renal insufficiency, bronchial cancer and other diseases.

One of the main causes of hyperprolactinemia is pituitary tumors. This is because the tumor is composed of prolactin-secreting cells, which are out of control and secrete prolactin without restraint. At the same time, prolactin can also increase due to factors such as compression of the pituitary stalk.

If the level of prolactin in the blood is too high, it is called hyperprolactinemia. These people often have symptoms of breast tenderness, galactorrhea, scanty menstruation or even amenorrhea. Therefore, it is sometimes called galactorrhea-amenorrhea syndrome. Among patients with hyperprolactinemia, about 1/4 are caused by pituitary tumors, and some may be caused by hypothalamic and pituitary dysfunction, hypothyroidism, renal insufficiency, malignant tumors in other parts of the body, chest wall damage and drug effects.

Increased prolactin can significantly inhibit the normal secretion of pituitary gonadotropins (such as follicle-stimulating hormone and luteinizing hormone), affecting the normal development of follicles, ovulation function and pregnancy function. Reduced follicle-stimulating hormone secretion will directly lead to developmental disorders of ovarian follicles, weak or incomplete development (B-ultrasound observation shows follicles with a diameter of less than 18 mm or less), and ultimately inability to conceive; while insufficient secretion of progesterone (luteinizing hormone) causes incomplete luteal function, making it difficult to maintain the fertilized follicles to continue implantation and development (such as testing the basal body temperature shows a low temperature phase below 36.8°C), making it difficult to get pregnant, and even if pregnancy occurs, miscarriage is likely to occur.

In addition, excessive prolactin can also cause the ovaries to lose their ability to respond to gonadotropins, resulting in a significant reduction in the synthesis of estrogen and progesterone, causing estrogen, which plays an important role in the conception process, to be at a low level, directly affecting the fertility function. When the sex hormones are reduced to a certain level, the patient will also experience many symptoms similar to those of menopause.