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 .
Comparison of the skeletal effects of the progestogens desogestrel and levonorgestrel in oral contraceptive preparations in young women: controlled, open, partly randomized investigation over 13 cycles.
AIM This 12-month study was conducted to evaluate the skeletal effects of two monophasic oral contraceptives containing 20 mug of ethinylestradiol and 100 mug of levonorgestrel ( LEVO ) or 150 mug of desogestrel ( DESO ) . METHODS Fifty-two women ( 18 - 24 years ) were r and omized into the  DESO group or the LEVO group ; 36 women served as controls . The areal bone mineral density ( aBMD ) of the femoral neck and the lumbar spine was evaluated by DXA , and parameters of bone geometry and volumetric bone mineral density ( vBMD ) were assessed by peripheral quantitative computed tomography at the distal radius and the tibia . RESULTS The LEVO group did not lose vertebral aBMD , whereas women in the DESO group lost 1.5 % . At the distal radius and the tibia ( shank level , 14 % ) , LEVO induced an increase in total cross-sectional area , indicating increased periosteal bone formation . Radial trabecular vBMD declined by 1.4+/-1.8 % in the DESO group , while it remained unchanged in the LEVO group . CONCLUSION Our study suggests that the skeletal effects of OC preparations may be influenced by progestogenic components in young women
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 .