I remember when “The Pill”, as it is called, came out in the 60’s. It changed a lot of things. I doubt the male version will have as big of effect but it’s still interesting:
Men concerned about contraception may soon be able to use the male equivalent of the Pill, without the potential side-effects of a drug based on altering the balance of sex hormones.
Scientists have developed a chemical contraceptive that temporarily blocks the development of sperm but does not interfere with testosterone levels.
Trials on laboratory animals have shown that the contraceptive effect is reversible and that there are no apparent long-term side-effects. Human trials of the new male contraceptive could begin within the next few years.
The biggest change I predict will be the child support issues that arise when the man thinks his female sex partner is using some sort of birth control when in fact she was careless or even deliberately not using something. The man now has a means to protect himself from unwanted pregnancies of that sort while still preserving his options for a child at a later date.