Inhibin A

Inhibin is a protein secreted by the Sertoli cells in men and granulosa cells in women. Its function is to inhibit the synthesis and release of the FSH (Follicule Stimulation Hormone) in the pituitary gland and reduces the hypotalamic LH (Leutenising Hormone) content. In general, Inhibin A is associated with egg production and development. It stimulates the oocytes (immature egg cells) in woman’s ovaries. It is made by the placenta during pregnancy. It is measured as a screening test, to see if the baby has Down syndrome. Inhibin B also stimulates the developmant of sperm in men.
Interpretation:Serum Inhibin a and B levels fluctuate during the menstrual cycle. Inhibin A is low in early follicular phase and peaks at the ovulatory phase. A high Inhibin A level or higher than 1.6 MoM (Multiple of Median) is identifies as a 70% possibility of Down syndrome pregnancy at a false positive rate of 22% meaning that a high Inhibin level points out a Down syndrome pregnancy but 22% of the high results give healthy birth. Inhibin A test is a component of the second trimester (Quadruple Test) Down Syndrome testing parameters (AFP, hCG, uE3) and mostly ınterpreted together with a screening risk report (Ref Down Syndrome Screening Test)
Sample: Arm vein blood. Nonfasting
Working day: Everyday
Result Time: 2 days 6:00 PM