Androgen deficiency in women; role of accurate testosterone measurements.

Androgen deficiency in women has been recognized as a distinct clinical syndrome that affects thousands of women particularly women in the postmenopausal period of their life. This syndrome has been described by several names including female androgen deficiency syndrome as well as hypoactive, sexual desire disorder. A recent large survey concerning sexual problems in women also adds personal distress as a potential contributor to the low sexual desire found in some women with sexual dysfunction. Recognition of an androgen deficiency syndrome however, has been controversial and limited to a clinical diagnosis due to the lack of accurate and sensitive methods for measuring androgens in women. Up until now, available methods for measuring the sex steroids have been dependent on antibody based assays that employ a range of different detection systems including the use of isotopes such as tritium and I-125 or chemical signalling molecules that produce chemiluminescence. These assays have become increasingly more sensitive for the measurement of testosterone but are still incapable of providing the proper low-end sensitivity for analyzing testosterone in female blood specimens. Assays for testosterone performed either manually or with highly automated immunoassay instruments have been used to measure testosterone in women but with varying degrees of success. Existing immunoassay-based methods are quite adequate for measuring testosterone levels in males but lack sufficient sensitivity to accurately and reproducibly measure testosterone in females and pre-pubertal children. Recent advances with the use of ultrasensitive methods such as mass spectrometry coupled to either gas or liquid chromatography have improved the technology for measuring testosterone and other low concentration sex steroids like estradiol to the degree that mass spectrometry based methods are now capable of measuring the testosterone levels found in normal women and in women with extremely low levels of testosterone as observed in a true androgen deficiency disorder. This application of mass spectrometry for measuring testosterone should allow clinicians to better define female androgen deficiency and facilitate further investigation in the diagnosis and optimal management of androgen deficiency in women.