The use of steroids in the MLB should be banned, as they are now.

Mind, "libido" is not the only "reproductive-system" issue: there is (in what percentage of users I am unsure) some shrinkage of the testicles. What the literature says about it is that it is not drastic, and is fully reversible. It is accompanied by reduced fertility, also reversible. Whether having lowered chances of becoming a father while using steroids is a negative or a positive will, of course, depend on individual circumstances; but none of this rises to the level of "a serious problem".

Steroids, Other "Drugs", and Baseball

Frank Thomas also issued a statement saying that he had not used steroids.

Congress Opens Hearings on Steroid Use in Baseball

In short, the conclusion that seems to be in order are that steroid use by athletes can have some modest effects on the cardiovascular system, but that those effects are not notablysevere or necessarily even dangerous--in fact, possibly beneficial.

Medical Effects of PEDs - steroids and baseball

It is something from difficult to impossible to make even a decent estimate of what proportion of muscle added by steroid use is upper- versus lower-body, but we do know, verydefinitely, from copious comments in the scientific literature that steroid use very heavily favors upper-body musculature. (As the inimitable Casey Stengelfamously said, "you could look it up"--or just check here.) This is vital, so let me repeat it yet again, in an emphasis box:

In the 1930’s, steroids were known to be used for homosexuals to lower there testosterone....

Mitchell unveils web of steroid use in baseball - SFGate

Some believe that it is time to legalize the use of steroids in professional sports. As the statistics show, however, legalizing drug use for professional athletes would very likely increase teen athlete use of steroids.

Mitchell unveils web of steroid use in baseball ..

Steroids might enhance an athlete’s performance, but the costs may be high. That’s why the statistics of steroid use in athletes show that now is the time to stop turning a blind eye to the practice.

The committee also heard from the parents of Rob Taylor, a baseball player from Southern  who used steroids and committed suicide.

The Spread of Steroids in Baseball - Orgnet

Second, it completely ignores all the literature--discussed farther above under "psychiatric" issues--that some small but definite percentage of steroid users are users exactlybecause they had mental problems of one sort of another coming into usage. Some of those problems are the sort that lead to a spectrum of high-risk activities in a manner thatsuggests "addiction" not to this or that activity but to risk itself. Others have personality problems of another sort, typically , which is effectively the obverse of anorexia. Such persons will seem"addicted" to steroids (and, in the first sort, a collection of other things) for reasons totally unrelated to the effects or chemistry of steroids. To say steroids are "theproblem" for such people is like saying food is "the problem" for an anorexic--and to imply otherwise is intellectual dishonesty of a high order.

It is in this hyper-competitive environment that a growing specter of foul play has erupted – the use of steroids....

Steroid Use in Baseball: Players - YouTube

(It is also worth remembering, for perspective, that ; in other words, everyday Tylenol is a substantially more serious liver risk than any steroid. Major-LeagueBaseball is scarcely likely to ban Tylenol use despite that known, documented risk (which is far graver than steroids).

Steroids - Anabolic Steroids in Major League Baseball ..

Another issue that faces athletics and steroid use is the fact that most states don’t require testing for them in the student athlete population. Only 4 states in the US in 2008 had a mandated testing program, which meant that an athlete could easily get away with steroid use. That creates a sense of invincibility that translates into the professional realm and leads to the attitudes of steroid use that are being seen today.