Testosterone can be administered parenterally , but it has more irregular prolonged absorption time and greater activity in muscle in enanthate , undecanoate , or cypionate ester form. These derivatives are hydrolyzed to release free testosterone at the site of injection; absorption rate (and thus injection schedule) varies among different esters, but medical injections are normally done anywhere between semi-weekly to once every 12 weeks. A more frequent schedule may be desirable in order to maintain a more constant level of hormone in the system.  Injectable steroids are typically administered into the muscle, not into the vein, to avoid sudden changes in the amount of the drug in the bloodstream. In addition, because estered testosterone is dissolved in oil, intravenous injection has the potential to cause a dangerous embolism (clot) in the bloodstream.
THANK YOU!! I fucking irks me to no end when I see someone spewing off nostalgic vitriol about how the Edwardian era and the 1950s was some sort of heaven on earth for those of the penis-posessing variety. IT WAS NOT. In fact it was far from it. Want to talk about gender roles? How about the MALE gender roles. Men were regulated to cannon fodder who were obligated to lay down their lives in the trenches of France and Belgium during WW1 because their respective European emperors told them to because of a bitchfest that was simmering with the other European emperors. Ditto for the Vietnam war 50 years later. And a few years earlier they were obligated to freeze to death in the Atlantic ocean as the Titanic sank under them because the life of a man was apparently less valuble than that of a woman or child.