Primary hypogonadism (congenital or acquired): Testicular failure due to diseases and conditions in the body such as cryptorchidism, bilateral torsion, orchitis, vanishing testis syndrome, orchiectomy, Klinefelter Syndrome, chemotherapy, or toxic damage from alcohol or heavy metals; these men usually have low serum testosterone levels and gonadotropins (FSH, LH) above normal range Hypogonadotropic hypogonadism (congenital or acquired): Gonadotropin or luteinizing hormone-releasing hormone (LHRH) deficiency or pituitary-hypothalamic injury from tumors, trauma, or radiation; these men have low testosterone serum concentrations but have gonadotropins in the normal or low range.
There are several relatively simple lifestyle changes a woman can make that might elevate T levels. Most obviously, if a woman believes her birth control pills are causing a problem and she feels she can adjust to a different type of birth control, she might stop using them (if indeed she's using them exclusively to prevent conception). She might also reevaluate her need for any of the various medications I mentioned, and perhaps seek alternatives that might not affect testosterone levels. For instance, there's some evidence that the antidepressant wellbutrin actually increases libido, but whether it helps the sex mojo through raising T levels or by some other mechanism isn't well understood.