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Administration of luteinizing hormone (LH) (or human chorionic gonadotropin) and follicle-stimulating hormone (FSH) is very effective in the treatment of male infertility due to hypogonadotropic hypogonadism. Although controversial, off-label clomiphene citrate, an antiestrogen, may also be effective by elevating gonadotropin levels.
Though androgens are absolutely essential for spermatogenesis and therefore male fertility, exogenous testosterone therapy has been found to be ineffective in benefiting men with low sperm count. This is thought to be because very high local levels of testosterone in the testes (concentrations in the seminiferous tubules are 20- to 100-fold greater than circulating levels) are required to mediate spermatogenesis, and exogenous testosterone therapy (which is administered systemically) cannot achieve these required high local concentrations (at least not without extremely supraphysiological dosages). Moreover, exogenous androgen therapy can actually impair or abolish male fertility by suppressing gonadotropin secretion from the pituitary gland, as seen in users of androgens/anabolic steroids (who often have partially or completely suppressed sperm production). This is because suppression of gonadotropin levels results in decreased testicular androgen production (causing diminished local concentrations in the testes) and because FSH is independently critical for spermatogenesis. In contrast to FSH, LH has little role in male fertility outside of inducing gonadal testosterone production.
Estrogen, at some concentration, has been found to be essential for male fertility/spermatogenesis. However, estrogen levels that are too high can impair male fertility by suppressing gonadotropin secretion and thereby diminishing intratesticular androgen levels. As such, clomiphene citrate (an antiestrogen) and aromatase inhibitors such as testolactone or anastrozole have shown effectiveness in benefiting spermatogenesis.
Low-dose estrogen and testosterone combination therapy may improve sperm count and motility in some men, including in men with severe oligospermia.
Treatments vary according to the underlying disease and the degree of the impairment of the male fertility. Further, in an infertility situation, the fertility of the female needs to be considered.
Pre-testicular conditions can often be addressed by medical means or interventions.
Testicular-based male infertility tends to be resistant to medication. Usual approaches include using the sperm for intrauterine insemination (IUI), in vitro fertilization (IVF), or IVF with intracytoplasmatic sperm injection (ICSI). With IVF-ICSI even with a few sperm pregnancies can be achieved.
Obstructive causes of post-testicular infertility can be overcome with either surgery or IVF-ICSI. Ejaculatory factors may be treatable by medication, or by IUI therapy or IVF.
Vitamin E helps counter oxidative stress, which is associated with sperm DNA damage and reduced sperm motility. A hormone-antioxidant combination may improve sperm count and motility. However there is only some low quality evidence from few small studies that oral antioxidants given to males in couples undergoing in vitro fertilisation for male factor or unexplained subfertility result in higher live birth rate. It is unclear if there are any adverse effects.
Tamoxifen, a selective estrogen receptor modulator (SERM) with antiestrogenic actions in breast tissue and estrogenic actions in bone, has been found to be highly effective in preventing and reversing bicalutamide-induced gynecomastia in men. Moreover, in contrast to analogues (which also alleviate bicalutamide-induced gynecomastia), tamoxifen poses minimal risk of accelerated bone loss and osteoporosis. For reasons that are unclear, anastrozole, an aromatase inhibitor (or an inhibitor of estrogen biosynthesis), has been found to be much less effective in comparison to tamoxifen for treating bicalutamide-induced gynecomastia. A systematic review of -induced gynecomastia and breast tenderness concluded that tamoxifen (10–20 mg/day) and radiotherapy could effectively manage the side effect without relevant adverse effects, though with tamoxifen showing superior effectiveness. Surgical breast reduction may also be employed to correct bicalutamide-induced gynecomastia.
Combination of bicalutamide with medical (i.e., a analogue) or surgical castration modifies the side effect profile of bicalutamide. Some of its side effects, including breast pain/tenderness and gynecomastia, are far less likely to occur when the drug is combined with a analogue, while certain other side effects, including hot flashes, depression, fatigue, and sexual dysfunction, occur much more frequently in combination with a analogue. It is thought that this is due to the suppression of estrogen levels (in addition to androgen levels) by analogues, as estrogen may compensate for various negative central effects of androgen deprivation. If bicalutamide is combined with a analogue or surgical castration, the elevation of androgen and estrogen levels in men caused by bicalutamide will be prevented and the side effects of excessive estrogens, namely gynecomastia, will be reduced. However, due to the loss of estrogen, bone loss will accelerate and the risk of osteoporosis developing with long-term therapy will increase.
Hypospermia is a condition in which a man has an unusually low ejaculate (or semen) volume, less than 1.5 ml. It is the logical opposite of hyperspermia. It should not be confused with oligospermia, which means low sperm count.
Normal ejaculate when a man is not drained from prior sex and is suitably aroused, is around 1.5-6 ml, although this varies greatly with mood, physical condition and sexual activity. Of this, around 1% by volume is sperm cells. Hypospermia would only usually be a factor in infertility if the two conditions (hypospermia and oligospermia) are combined. The U.S. based National Institutes of Health defines hypospermia as a semen volume lower than 2 mL on at least two semen analyses.
The presence of high levels of fructose (a sugar) is normal in the semen and this comes almost entirely from the seminal vesicle. The seminal vesicles, major contributors to ejaculate volume, render semen pH basic. Thus, low fructose may indicate problems in the prostatic pathway, while low semen pH may indicate problems related to the seminal vesicles. Obstruction of the seminal vesicles result in low semen volumes since they normally produce 70% of the seminal plasma.
In medicine, hyperspermia is a condition in which a male has an abnormally large ejaculate (or semen) volume. Males with hyperspermia usually have higher sex drives than males that do not. It is the opposite of hypospermia, and is generally defined in humans when the ejaculate is over 5.5 ml.