When should the prolactin test be done? Which day of the cycle?

The pituitary gland produces it, and having too much of it (hyperprolactinemia) can result in infertility, galactorrhea, low libido, and excessive hair growth. 10–40% of women who don’t have periods have too much prolactin in their bodies.

How do I test the level of prolactin?

The doctor orders a blood prolactin test because he/she thinks the patient has hyperprolactinemia. This test can be done at any time during a woman’s cycle. You should have breakfast before you go to the blood test in the morning. You shouldn’t work out, have sex, or do anything else to your nipples. You should also avoid stress.

Let us remind you that the correct level of prolactin depends on the phase of the cycle and is:

• follicular phase – below 23 µg/l,
• lutein phase – below 40 µg / l,
• third trimester of pregnancy – up to 400 µg/l.

If the amount of prolactin in the blood is too high (more than 20-25 ng/ml), further testing is needed: First, it should be looked into whether or not the woman:

• she is not pregnant
• there is no hypothyroidism ,
• does not take medications that may increase the level of prolactin in the blood.

The next step is to use metoclopramide to do a functional test. Functional hyperprolactinemia is diagnosed if the amount of prolactin in the blood goes up by more than six times after taking the tablet. If the growth is smaller, an MRI must be done on the pituitary gland, where a tumor may be present.

Elevated prolactin

The body makes too much prolactin sometimes in response to things like stress, sleep, nipple stimulation, and sexual activity. When these things happen to a healthy person, the hormone level goes up a little bit. This is called “functional hyperprolactinemia.

The pituitary gland may also send out too much prolactin in the following situations:

• there is a tumor in the pituitary gland (the so-called pituitary adenoma , prolactinoma) that secretes a hormone,
• the liver or kidneys do not work properly – they are unable to metabolize prolactin, which leads to its accumulation,
• in hypothyroidism,
• while taking certain medications (e.g. antidepressants, antihypertensives), after discontinuation of hormonal contraceptives.

Menstrual disorders

How you feel depends on how much prolactin is in your blood. Most of the time, menstrual problems are the first to show up. Menstrual bleeding becomes irregular, and the time between periods gets longer and longer. Menstruation can be very light or very heavy, depending on the person. Most of the time, these disorders are accompanied by infertility and a lower libido.

Galactorrhoea and excessive hair growth

Then galactorrhoea may happen, which is when a woman who is not breastfeeding has milk in her breasts. Hyperprolactinemia can also cause hair to grow too quickly. As we’ve already said, a tumor in the pituitary gland is one of the things that can cause hyperprolactinemia. If the tumor is big, it can cause headaches and a narrowing of the field of vision.

see also : High prolactin levels and weight gain: how does prolactin affect appetite and shape?