There are two ways that hormones can help the doctor check a baby or young boy for undescended or absent testicles.
One way is a blood test that checks the levels of certain
hormones, including one called Müllerian-inhibiting substance (MIS). The test results can help the doctor tell if the testicles are present and undescended or if they are absent (anorchia).
produced by the testicles and can be detected in a blood sample from a boy
until he reaches
puberty. If a boy who has an undescended testicle has
measurable MIS in his blood, it is a good sign that one or both testicles are
present. If MIS cannot be detected in the boy's blood, then both testicles are
Blood tests may also check the levels of two other hormones: luteinizing hormone (LH) and
follicle-stimulating hormone (FSH). When the testicles are absent, these hormone levels are both higher than
A second way to check for undescended or absent testicles is to get an injection of human chorionic gonadotropin (hCG) hormone for a few days. This hormone stimulates the
testicles to release
testosterone. The doctor then will check if testosterone levels go up. If both the testicles are absent, testosterone
levels will not increase. HCG
also stimulates enlargement of the testicles, making it easier to locate the
testicle during a physical examination.
Sometimes the results of these tests are not clear. For example, a boy may have normal levels of LH and FSH, but the hCG test does
not produce an increase in testosterone. If the results are
not clear, the doctor may need to do surgery to find and evaluate the undescended
ByHealthwise Staff Primary Medical ReviewerJohn Pope, MD - Pediatrics Anne C. Poinier, MD - Internal Medicine Adam Husney, MD - Family Medicine Specialist Medical ReviewerPeter Anderson, MD, FRCS(C) - Pediatric Urology