Samples are sent frozen to Awanui, Auckland (LTA) for analysis.
External requests are not to be collected at LabPLUS , these patients are to be directed to Awanui labs as this is patient funded.
Hospital requests may be vetted by a pathologist.
If an external requestor is being advised to test by a hospital specialist, this is to be clearly documented on the form
Declined tests :
If a test is declined, the specimen will be held for a reasonable period (usually 3 weeks but dependant on the stability of the sample). Medical practitioners seeking approval for a declined test should email the on-call Chemical Pathologist ( chemicalpathologist@adhb.govt.nz ) , giving the patient's name and NHI number and the clinical justification for the test. If unable to email, call the on-call Chemical Pathologist via Lablink (09-3078995) and identify yourself as a doctor.
Diagnostic Use and Interpretation
Assessing fertility
In adult women serum levels are related to the number and activity of follicles and low levels correlate with declining ovarian reserve with aging, especially though the perimenopausal transition.
AMH levels vary little throughout the natural menstrual cycle and can be interpreted regardless of the time of collect (however, levels do fall during the follicular phase of FSH-induced cycles). This stability of AMH contrasts with other hormones such as FSH and inhibin sometimes used to assess ovarian reserve and which should be measured on day 3 of the menstrual cycle.
In females levels are undetectable at birth, and remain during childhood. They rise rapidly during puberty, fall slowly through adulthood as ovarian follicle numbers decline, and are typically undetectable after menopause or bilateral oophorectomy.
fertility potential AMH (pmol/L) AMH (ng/mL)
optimal fertility 28.6 - 48.5 4.0 - 6.8
satisfactory fertility 15.7 - 28.6 2.2 - 4.0
low fertility <15.7 48.5 >6.8
Other rare uses
AMH is present in about 75% of granulosa tumours and can be used in detection and monitoring after surgery or chemotherapy. Even extremely high levels usually fall to normal days to weeks after surgery (serum half-life about 30 hr). It is also secreted by some sex chord tumours and Sertoli-Leydig cell tumours.
Levels may also be helpful in the evaluation of boys with cryptorchidism and possible intersex states, where a positive result suggests presence of testicular tissue and a high level may indicate disorders of testosterone synthesis and androgen resistance (complete/partial androgen insensitivity).
Use of this test should be reserved for specialist settings.
Ref: Lane AH. Diagnostic utility of Mullerian inhibiting substance determination in patients with primary and recurrent granulose cell tumors. Gynecol. Oncol. 1999; 73:51-55