Low dosages used in Hormone Replacement Therapy (HRT) can definitely lower sperm count in normal men.
You need both LH & FSH for normal spermatogenesis, using Human Chorionic Gonadotropin ( Human Chorionic Gonadotropin (HCG) ) during the cycle will only enable you to maintain Leydig cell volume/ testosterone-secreting capacity, but it won't prevent a decrease of sperm count....
J Clin Endocrinol Metab 1990 Jan;70(1):282-7 Related Articles, Links
Effects of chronic testosterone administration in normal men: safety and efficacy of high dosage testosterone and parallel dose-dependent suppression of luteinizing hormone, follicle-stimulating hormone, and sperm production.
Matsumoto AM.
Geriatric Research, Education, and Clinical Center, Veterans Administration Medical Center, Seattle, Washington 98108.
In normal men, chronic testosterone (T) administration results in negative feedback suppression of gonadotropin and sperm production. However, azoospermia is achieved in only 50-70% of men treated with high dosages of T. Furthermore, the relative sensitivity of LH and FSH secretion to chronic administration of more physiological dosages of T is unclear. We determined whether a T dosage higher than those previously given would be more or less effective in suppressing spermatogenesis and whether, within the physiological range, T would exert a more selective effect on LH than on FSH secretion. After a 4- to 6-month control period, 51 normal men were randomly assigned to treatment groups (n = 9-12/group) receiving either sesame oil (1 mL) or T enanthate (25, 50, 100, or 300 mg, im) weekly for 6 months. Monthly LH and FSH levels by RIA and twice monthly sperm counts were determined. During treatment, T levels were measured daily between two weekly injections. Chronic T administration in physiological to moderately supraphysiological dosages resulted in parallel dose-dependent suppression of LH, FSH, and sperm production.T enanthate (50 mg/week) suppressed LH and FSH levels and sperm counts to 50% of those in placebo-treated men (ED50). T enanthate (300 mg/week), was no more effective than 100 mg/week in suppressing LH, FSH, and sperm production. Serum T levels in men who received 100 and 300 mg/week T enanthate were 1.5- and 3-fold higher than those in placebo-treated men, respectively. Except for mild truncal acne, weight gain, and increases in hematocrit, we detected no significant adverse health effects of chronic high dosage T administration. We conclude that 1) LH and FSH secretion are equally sensitive to the long term negative feedback effects of T administration; 2) sperm production is suppressed in parallel with the LH and FSH reductions induced by chronic T administration; and 3) even at the clearly supraphysiological dosage of 300 mg/week, T enanthate does not reliably induce azoospermia in normal men. However, there was also no evidence of a stimulatory effect of this T dosage on spermatogenesis. Furthermore, we found no evidence of major adverse health effects of T administered chronically even at the highest dosage.
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J Clin Endocrinol Metab 1986 Jun;62(6):1184-92 Related Articles, Links
Chronic human chorionic gonadotropin administration in normal men: evidence that follicle-stimulating hormone is necessary for the maintenance of quantitatively normal spermatogenesis in man.
Matsumoto AM, Karpas AE, Bremner WJ.
The role of FSH in the maintenance of spermatogenesis in man is poorly understood. To determine whether normal serum levels of FSH are necessary for the maintenance of quantitatively normal spermatogenesis, we first studied the effect on sperm production of selective FSH deficiency induced by chronic administration of hCG in normal men. Then, we determined the effect of FSH replacement in some of these men. After a 3-month control period, eight normal men (aged 30-39 yr) received 5000 IU hCG, im, twice weekly for 7 months. Then while continuing the same dosage of hCG, subjects simultaneously received 200 mg testosterone enanthate (T), im, weekly for an additional 6 months. hCG administration alone resulted in partial suppression of the mean sperm concentration from 88 +/- 24 (+/-SEM) million/ml during the control period to 22 +/- 7 million/ml during the last 4 months of hCG treatment (P less than 0.001 compared to control values). With the addition of T to hCG, sperm counts remained suppressed to the same degree. Except for one man who became azoospermic while receiving hCG plus T, sperm motilities and morphologies remained normal in all subjects throughout the entire study. During both the hCG alone and hCG plus T periods, serum FSH levels were undetectable (less than 25 ng/ml), and urinary FSH levels were comparable to those in prepubertal children and hypogonadotropic hypogonadal adults. We replaced FSH activity in four of the eight men in whom prolonged selective FSH deficiency and partial suppression of sperm production were induced by hCG administration. Immediately after the period of hCG plus T administration, T was stopped in four men who continued to receive hCG alone (5000 IU, im, twice weekly) for 3 months. Then, while continuing the same dosage of hCG, these men received 100 IU human FSH, sc, daily (n = 2) or 75 IU human menopausal gonadotropin, sc, daily (n = 2) for 5-8 months. During the second period of hCG administration alone, serum FSH levels were undetectable (less than 25 ng/ml), and sperm concentrations were suppressed (34 +/- 13 million/ml) compared to the control values for these four men (125 +/- 39 million/ml; P less than 0.001). With the addition of FSH to hCG, FSH levels increased (213 +/- 72 ng/ml) and sperm concentrations rose significantly, reaching a mean of 103 +/- 30 million/ml (P less than 0.03 compared to hCG alone).
