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 .
[Effect of ethinyl estradiol-dienogest combination on serum androgen concentrations].
Anti and rogens or progestins with an anti and rogenic component usually have only a weak antigonadotropic activity . It is thus possible that the anti and rogenic effect on the cellular level is cancelled or at least reduced by an increased ovarian and rogen production . The aim of the four su bmi tted clinical studies of the progestin and anti and rogen dienogest alone ( 0.5 - 2 mg/day ) or of a combined regimen of ethinylestradiol ( 0.03 mg ) plus dienogest ( 2 mg ) ( EE/DNG ) was to examine the influence on the serum and rogen and SHBG concentrations as well as on the serum FSH , LH , progesterone and 17 beta-estradiol concentrations in young women . Like the progesterone derivatives , dienogest has a relatively low antigonadotropic activity . Inhibition of ovulation is mainly produced by peripheral mechanisms such as the reduction of preovulatory 17 beta-estradiol secretion .  Dienogest alone has no significant effects on the serum SHBG and and rogen concentrations . Unlike this , the combination of EE plus DNG markedly increases SHBG concentrations ( to 2.1 - 3.7 fold the basal levels ) . The decrease in serum and rogens with total testosterone ( by 17 and 40 % ) , free testosterone ( by 48 and 54 % ) and dehydroepi and rosterone sulfate ( by 51 % ) corresponds to the values shown in the literature for other oral contraceptives with modern progestins . EE/DNG does not affect the serum concentrations of 5 alpha-dihydrotestosterone ( DHT ) , although the marker of the peripheral transformation from T to DHT , and rostanediol glucuronide , is distinctly reduced ( by 38 % ) . In a double-blind comparison no differences are found between EE/DNG and a regimen combining 0.02 mg of ethinylestradiol and 0.150 mg of desogestrel . Solely the SHBG concentrations , with EE/DNG , as expected , are significantly higher . In a sequential regimen , dienogest , chlormadinone acetate and desogestrel ( progestins without binding to SHBG ) enhance the inhibitory effect of ethinylestradiol sulfonate on free testosterone , whereas norethindrone acetate and levonorgestrel ( progestins with a strong binding to SHBG ) reduce this effect of the estrogen significantly . These results exclude the possibility that the very distinct anti and rogenic effect of dienogest on a cellular level is neutralised or reduced by an increased systemic supply of and rogen
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 .