What is pooled prolactin?

What is pooled prolactin?

“Pooled prolactin is a obsolete name“, emphasizes Dr. Véronique Raverot, Pharmacist Biologist, member of the French Society of Endocrinology. When this examination is prescribed, it triggers the prolactin assay on several samples (often 3) made about twenty minutes apart. Synthesized by the cells of the anterior pituitary, prolactin is a hormone which plays an essential role in the preparation and stimulation of lactation.

Why dose it?

“The blood assay of prolactin is carried out in the presence of clinical signs that may suggest a hyperprolactinemia.“In women it may be menstrual period disorders : amenorrhea or scanty and spaced periods. It is also performed during galactorrhea (discharge from the breasts). “In men, signs of hyperprolactinemia can be erectile dysfunction or low libido.“But there are also pituitary diseases (adenomas), which also require measuring prolactin. “Likewise, in case of osteoporosisa prolactin assay may be necessary as part of a bone assessment“, continues Véronique Raverot. Physiologically, its rate is higher during pregnancy in order to prepare the body for lactation, but there are also drugs that can generate an increase in prolactin, in particular neuroleptics.

“Since prolactin is secreted rather at the end of the night, it is advisable to go to the lab in the morning to perform the assay by blood test.“If the first sample is normal, then no need to take any more. On the other hand, if there is an increase in the prolactin concentration on this first assay, the result can be checked during a second sample taken at the end of the morning.

What does a high pooled prolactin level mean?

“A high prolactin level is called hyperprolactinemia.” Prolactin results vary with each lab but in general the normal rate is 5 to 20 ng/mL, and it can reach 250 ng/mL at the end of pregnancy. Although standards vary from lab to lab, it is between 1 and 15 nanograms/mL after menopause. The reference values ​​with another unit are 100 to 500 mIU/l in women, and 85 to 325 mIU/l in men. “Outside pregnancy, various diseases can cause an increase in the blood level of prolactin, in particular pathologies related to the pituitary gland. Sometimes it’s just a stress or intense physical exercise which increases prolactin.“Some drugs cause an elevation of prolactin. In other cases, no cause is found.”Beware, however, of a classic analytical interference on the prolactin assay: this is the presence of macro-prolactin which can be detected with certain reagents but which is not biologically active.” In effect, macro-prolactin may cause elevated prolactin levels in asymptomatic patients.

What to do in case of high rate?

Excluding pregnancy, it is a level greater than 25 ng/mL in women, or 15 ng/mL in men. “This hormone being secreted by the pituitary gland, it is necessary to consult to look for pituitary pathologies. In all cases and depending on the medical assessments, this requires management by the expert endocrinologist“, concludes the expert.

Thanks to doctor Véronique Raverot, Pharmacist Biologist, member of the French Society of Endocrinology