In this study test was reduced 69 % and LH was reduced 50 % after two months of 15 mg dianabol ED.
Acta Endocrinol (Copenh) 1976 Dec;83(4):856-64 Related Articles, Links
Effect of an anabolic steroid (metandienon) on plasma LH-FSH, and testosterone and on the response to intravenous administration of LRH
Holma P, Adlercreutz H.
Holma P, Adlercreutz H.
Plasma levels of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) as well as the response of LH and FSH to the intravenous administration of 100 mug of luteinizing hormone releasing hormone (LRH) were measured in 16 well-trained athletes (mean age 30 years) before and after 2 months of daily oral intake of 15 mg of metandienon...
During administration of metandienon the mean plasma testosterone level fell 69%, from 29.4 +/- 11.6 nmol/1 to 9.1 +/- 7.5 nmol/1 The mean plasma levels of LH and FSH also fell significantly (P less than 0.001 and P less than 0.01, respectively), both about 50%.
Other orals also cause significant suppression at low doses:
Clin Endocrinol (Oxf) 1984 Jul;21(1):49-55 Related Articles, Links
Alteration of hormone levels in normal males given the anabolic steroid stanozolol.
Small M, Beastall GH, Semple CG, Cowan RA, Forbes CD.
...Its endocrine effects have received little attention and we have investigated the effect of administering a
14 d course of stanozolol (10 mg orally per day) on a variety of important hormonal pathways in nine healthy male subjects. Significant changes occurred as follows:
a 55% reduction in serum testosterone levels was noted and was accompanied by reductions in 'derived' free testosterone, sex hormone binding globulin and LH levels...
Oxandrolone causes significant suppression at 15mg ED within 5 days:
from:
http://jcem.endojournals.org/cgi/content/full/84/8/2705
...Total serum T concentrations were within normal physiological range on day 0 (449 ± 35 ng/dL) and day 3 (441 ± 44 ng/dL) of OX treatment.
However, by day 5, total serum T concentrations were significantly reduced (282 ± 45 ng/dL; P < 0.05) below day 0 and day 3 values (Fig. 3)...
Figure 3. Total androgen concentration. Total serum T (hatched portion) and OX (black portion) concentrations in five young men on days 0, 3, and 5. *, T decreased significantly from days 0 and 3 to day 5 (P < 0.05).