SHBG typically circulates at higher concentrations in women than in men, due to the higher ratio of estrogens to androgens in women. For the same reason, SHBG levels in late pregnancy or after estrogen administration may be especially elevated. Elevated SHBG may be encountered in hyperthyroidism and hepatic cirrhosis. High levels are also found in a variety of other conditions, such pregnancy.
It has been reported that women with high levels of sex hormone binding globulin – which reduces the activity of the sex hormones – were at decreased risk of breast cancer. The same study reported that women with the highest levels of estrogen and/or testosterone were twice as likely to develop breast cancer as those with the lowest levels. [Journal of the National Cancer Institute, 17th April 2002]