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 .
Effects of oral contraceptive combinations containing levonorgestrel or desogestrel on serum proteins and androgen binding.
The effects of the oral contraceptive combinations 0.125 mg Org 2969 ( desogestrel ) ( 13-ethyl-11-methylene-18,19-dinor-17alpha-pregn-4-en-20-yn-17-ol ) + 0.05 mg ethinyloestradiol ( EE ) and 0.125 mg levonorgestrel + 0.05 mg EE on serum sex-hormone-binding globulin ( SHBG ) , ceruloplasmin , transcortin and ratio free testosterone over total testosterone ( percentage free testosterone ) and ratio free 5alpha-dihydrotestosterone over total 5alpha-dihydrotestosterone ( percentage free 5alpha-dihydrotestosterone ) were compared in healthy female volunteers . Treatment was r and omly distributed over the volunteers ; 11 women received  Org 2969 + EE  and 11 women received  levonorgestrel + EE . These combinations induced similar increases in transcortin levels ( 115 and 140 % ) and ceruloplasmin levels ( 115 and 123 % ) after 3 months of treatment . However , the combination Org 2969 + EE induced a substantial increase ( 213 % ) in SHBG capacity after 3 months of treatment , whereas a smaller increase ( 80 % ) was observed with levonorgestrel + EE . A return to pretreatment values was observed 2 months after termination of treatment for all parameters . The difference in the effects of both preparations oh SHBG was statistically significant and can be best explained by a difference in the and rogenicity of the progestogens . A good correlation was free testosterone and the reciprocal value of the percentage free 5 alpha-dihydrotestosterone . These results confirm that SHBG is the major regulator of the biologically active free and rogen fraction in women before , during and after combined oral contraceptive treatment
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 .