healthymen101.comMale fertility is a complex situation. To get your partner pregnant, the following must happen:

You must produce healthy sperm.Initially, this has much to do with the growth and formation of the male reproductive organs during puberty. At least one of your testicles must be functioning properly, and your body must produce testosterone and other hormones to trigger and maintain sperm production.
Sperm have to be carried into the semen.Once sperm are produced in the testicles, delicate tubes transport them until they mix with semen and are ejaculated out of the penis.
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There needs to be enough sperm in the semen.If the number of sperm in your semen (sperm count) is reduced, it decreases the odds that one of your sperm will fertilize your partner’s egg. A low sperm count is fewer than 15 million sperm per milliliter of semen or fewer than 39 million per ejaculate.
Sperm must be functional and able to move.If the movement (motility) or function of your sperm is not normal, the sperm may not be able to reach or penetrate your partner’s egg.
Medical causes

Issues with male fertility can be created by a number of health issues and medical treatments. Some of these include:

A varicocele is a swelling of the veins that drain the testicle. It’s the most common reversible reason for male infertility. Although the exact reason that varicoceles cause infertility is not known, it may be related to abnormal testicular temperature regulation. Varicoceles result in reduced quality of the sperm.
Treating the varicocele can improve sperm numbers and function, and may potentially improve outcomes when using assisted reproductive techniques the likes of in vitro fertilization.

Some infections can tamper with sperm production or sperm health or can cause scarring that blocks the passage of sperm. These include inflammation of the epididymis (epididymitis) or testicles (orchitis) and some sexually transmitted infections, including gonorrhea or HIV. Although some infections can lead to permanent testicular damage, most often sperm can still be retrieved.
Ejaculation issues.Retrograde ejaculation happens when semen enters the bladder during orgasm instead of emerging out the tip of the penis. Various health conditions can make retrograde ejaculation, including diabetes, spinal injuries, medications, and surgery of the bladder, prostate or urethra.
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