Why haven't they made a male form of birth control yet?

Side effects: Well, there are condoms, getting a vasectomy and abstinence. Its fairly easy to stop a woman from ovulating by giving her a hormone her body makes anyway. That is essentially how a woman's birth-control pills work. But stopping sperm production is a major undertaking. So far, anything drastic enough to stop sperm production is damaging to the man who takes it. Many companies have tried.

They have: It's called a condom & been available is some form since the 16th century. As far as trying to stop production of 2 million sperm/d compared to release of one egg/mo, there are technical issues that make it unlikely.

Side effects.: In addition to what Dr.Ferguson stated, the pills that block the production of sperm have too many side effects. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.