Effects of oral and transdermal hormone replacement therapy on serum free testosterone levels in postmenopausal women

Abstract

Background: As a consequence of declining testosterone (T) production, many postmenopausal women (PMW) experience a variety of physical symptoms secondary to androgen depletion. Most of these symptoms are not improved with hormone replacement therapy (HRT). The route of estrogen administration may influence androgen levels as a result of varying effects on LH and SHBG. Oral estrogen (OE) administration decreases LH production, whereas SHBG is increased. The net result is a decrease in free T concentration. In contrast, the corresponding effects following parenteral estrogen administration are less well defined.