However , subgroup analyses for the estrogen dose and the progestin type in relation to changes in SHBG levels did show significant differences : COCs containing second generation progestins and /or the lower estrogen doses ( 20–25 µg EE ) were found to have less impact on SHBG concentrations .
The current literature review and meta- analysis demonstrates that COCs decrease circulating levels of total T and free T and increase SBHG concentrations .
Due to the SHBG increase , free T levels decrease twice as much as total T. The estrogen dose and progestin type of the COC do not influence the decline of total and free T , but both affect SHBG .
BACKGROUND Combined oral contraceptives ( COCs ) reduce levels of and rogen , especially testosterone ( T ) , by inhibiting ovarian and adrenal and rogen synthesis and by increasing levels of sex hormone-binding globulin ( SHBG ) .
Although this suppressive effect has been investigated by numerous studies over many years , to our knowledge no systematic review concerning this issue had been performed .
Diurnal rhythm and effects of oral contraceptives on serum dehydroepiandrosterone sulfate (DHEAS) are related to alterations in serum albumin rather than to changes in adrenocortical steroid secretion
Dehydroepi and rosterone sulfate ( DHEAS ) , which is of almost exclusive adrenal origin , is important for the and rogen status in women and prepubertal children , and DHEAS assays are used in the investigation of hyper and rogenism . There are conflicting reports concerning a diurnal variation in serum DHEAS . Although of adrenocortical origin , serum DHEAS levels are decreased by oral contraceptives ( OCs ) . DHEAS is strongly bound to serum albumin and has a very low metabolic clearance rate . The present study was performed in order to investigate whether a diurnal variation in serum DHEAS exists and , if so , whether this diurnal variation and the decreased DHEAS levels following OC use are related to alterations in adrenocortical steroids or to changes in serum albumin . Serum concentrations of DHEAS , dehydroepi and rosterone ( DHEA ) , cortisol and albumin were determined in blood sample s taken every half hour over a 24-h period in 10 healthy women before and during use of combined OCs .  Significant and frequently synchronous diurnal variations in serum DHEAS and albumin were found before as well as during OC use . These variations were not synchronous with the diurnal variation in DHEA . OCs significantly decreased serum DHEAS and albumin levels . A multiple regression analysis showed changes in albumin to be the most decisive factor for the diurnal variation as and for OC-induced changes in DHEAS . Changes in serum DHEAS during the day and following OC use are related to alterations in its main binding protein , serum albumin , rather than to changes in adrenocortical steroid secretion
However , subgroup analyses for the estrogen dose and the progestin type in relation to changes in SHBG levels did show significant differences : COCs containing second generation progestins and /or the lower estrogen doses ( 20–25 µg EE ) were found to have less impact on SHBG concentrations .
The current literature review and meta- analysis demonstrates that COCs decrease circulating levels of total T and free T and increase SBHG concentrations .
Due to the SHBG increase , free T levels decrease twice as much as total T. The estrogen dose and progestin type of the COC do not influence the decline of total and free T , but both affect SHBG .
BACKGROUND Combined oral contraceptives ( COCs ) reduce levels of and rogen , especially testosterone ( T ) , by inhibiting ovarian and adrenal and rogen synthesis and by increasing levels of sex hormone-binding globulin ( SHBG ) .
Although this suppressive effect has been investigated by numerous studies over many years , to our knowledge no systematic review concerning this issue had been performed .