Unfortunately, the same study that tells us that MENT is 10x as anabolic as testosterone, and 4x as androgenic, also tells us that MENT is 12x as suppressive to serum gonadatropins as testosterone. For this reason, it is very appealing to scientists who have studied it for use as a male contraceptive – and ended up calling it “ The Optimal Androgen for Male Contraception ” (Ann Med. 1993 Apr;25(2):199-205.). In addition, and partly owing to its inability to be 5a-reduced, MENT is converted (via the aromatase enzyme) to a very potent form of estrogen – which can cause gynecomastia (enlarged breast tissue in males), and several other nasty side effects.
Testosterone enanthate ( USAN , BAN ) (brand names Delatestryl , Testostroval , Testro LA , Andro LA , Durathate , Everone , Testrin , Andropository ), or testosterone heptanoate , is an androgen and anabolic steroid and a testosterone ester .    Along with testosterone cypionate and testosterone propionate , it is one of the most widely used testosterone esters.  Testosterone enanthate was first introduced in 1952.  Administered via intramuscular injection , it is the most widely used form of testosterone in androgen replacement therapy .