Testosterone is produced mainly by the testes and is essential for sperm production, libido and general male health; it is present at much lower levels in women, produced by the ovaries and adrenal glands. Total testosterone measures all testosterone in the blood, most of which is bound to sex hormone-binding globulin (SHBG); free testosterone estimates the smaller, biologically active unbound fraction, and is sometimes checked when total testosterone is borderline or SHBG is abnormal. Low testosterone in men (hypogonadism) can reduce sperm counts and is investigated alongside FSH and LH to identify whether the cause lies in the testes or in the pituitary/hypothalamus. Testosterone replacement therapy is not used to treat male infertility, because external testosterone can further suppress natural sperm production.
Also known as: low testosterone, free testosterone, SHBG, sex hormone binding globulin
Related India guides
Sources
- Indian Council of Medical Research (icmr.gov.in)
- Federation of Obstetric and Gynaecological Societies of India (fogsi.org)
Last reviewed: 9 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.