Systematic review and meta-analysis on the effect of the contraceptive pill on testosterone.
On 29 September 2013 the electronic version of the following paper has been published in Human Reproduction Update:
Y. Zimmerman, M.J.C. Eijkemans, H.J.T. Coelingh Bennink, M.A. Blankenstein and B.C.J.M. Fauser. The effect of combined oral contraception on testosterone levels in healthy women: a systematic review and meta-analysis. Human Reproduction Update, e-publication doi:10.1093; 29 Sept 2013
Combined oral contraceptives (COCs) reduce levels of androgen, especially testosterone (T), by inhibiting ovarian and adrenal androgen synthesis and by increasing levels of sex hormone binding globulin (SHBG). Although this suppressive effect has been investigated by numerous studies over many years, no systematic review concerning this issue had been performed.
The main conclusions were that COCs decrease circulating levels of total T by 31% and of free T by 61%. SBHG concentrations are increased by about 50-250%. Due to the SHBG increase, the free T levels decline twice as much as total T. The oestrogen dose and progestin type of the COC do not influence the decrease of total and free T, but both affect SHBG. The clinical implications of suppressed androgen levels during COC use remain to be elucidated.