When we talk about penis, it's enlargement then it is imperative to know about fertility. This is the process, which creates a new human life. Sperm from a man's body unites with women's egg to create a totally unique & genetically irreplaceable human life. It is an amazing process. Yet most men know very little about what contributes to reproductive health or conversely what undermines it. We seldom think about our fertility or the health of our sperm except perhaps during sexual activity. Yet science tells us we should consider our fertility & be protective of it. Indeed there are things we can do to safeguard our reproductive health and the well being our future children. It all starts with being more knowledgeable about our health in general and about behavior choices & environmental hazards that can adversely affect our reproductive well being. Fertility is not just the "woman's problem" anymore. It used to be and not so long ago, that if a couple was unable to conceive the woman was the infertility one. Now it is generally recognised with in medical circles the problems lies with the man in 35% of cases (some say a couple's inability to conceive is due male conditions 40% -50% of the time). The most common reason for in fertility in the male is the inability to produce adequate number of health sperm. Infertility in men may also be caused by problems delivering sperm into the vagina as occurs impotence or in disorders affecting ejaculation inhibited ejaculation & retrograde ejaculation (when ejaculation is forced backward into the bladder). It may also be caused damage the sperm producing structures or by antibodies to the sperm found in either the male or the female.

Obstacles to Fertilization: -  
A number of problems can prevent fertilization from taking place and many of these can indeed originate with the male. Major causes of male infertility is inability to produce enough healthy sperm. Your sperm must be present in sufficient volume, it must be active, it must not be clumping together, it must be relatively normal in shape & size and it must not be adversely affected by sperm anti bodies either in the man or in the woman. Further, it must be able to penetrate the woman's cervical mucus and over come staggering odds to ever even reach the fallopian tubes and go on to meet the egg.

The following list of "threats" to male fertility while certainly not all-inclusive will help you to avoid injurious substance situations and behavior.

Smoking (this significantly decreases both sperm count and the liveliness of sperm cells).

Prolonged use of marijuana.

Use of other "recreational" drugs like cocaine.

Chronic alcohol abuse

Use of anabolic steroids (excessive exercise may cause testicular shrinkage & infertility)

Overly intense exercise (excessive exercise may lower your sperm count by producing higher levels of ad renal steroid hormones which lower the amount of testosterone in the body. This testosterone deficiency in turn decreases sperm production).

In adequate vitamin c & zinc the diet

Some group of antibiotics (e.g. nitrofurans & macrolides).

Infection of reproductive system structures such as prostatitis epididymitis and orchids.

Infectious diseases that affect the testes such as mumps in adulthood.

Trauma or injury to the testes.

Exposure to Des (Diethylstil bestrol) during your mother's pregnancy, which can cause testicular & epididymal abnormalities & decreased sperm production.

Fever

Tight underwear or jogging pants.

Hot tubs saunas anything that raises the temperature of your scrotum including over heated vehicles & hot work environments.

A testosterone deficiency.

Exposure to environmental hazards such pesticides, lead, paint, radiation (X-ray) radioactive substances, mercury, benzene, boron and `heavy metals.

Chemotherapeuti (cancer-treating) agents.

Blockage or structural abnormality in the vas deferens.

Damage to the spermatic ducts, usually due to a sexually transmitted disease such as gonorrhea or chlamydia.

Malnutrition & anemia

Tuberculosis

Excessive stress.

Researchers now suspect that reproduction & fetal development may be affected if the biological father has been exposed to life style or occupation hazards such as smoking cigarettes drinking alcohol taking not- prescribed drugs, and being exposed to the toxic chemical.

It is therefore wish for men who want to have healthy children to change unhealthy life style habits & when possible protect themselves from hazards & toxins in the environment & work place.