he has a bad odor

hello ladies, if there is a doctor here or anyone who has experienced this and got an answer I would like some help. my boyfriends semen stinks. we had sex last night and immediately after I could smell the odor. its not the first time I've smelled it. last time it was actually causing a yeast infection. I didn't know what was causing it till he and i broke up. and I was dating here and there that's when I realized that it was my boyfriend. we did get back together and now its happening again. its been a year though since the last time. as much as I don't want to add this in i guess in order to get the correct answer I will, my boyfriend and i are about 25-30 years apart. her takes testosterone supplements such as powder and pills. is it possible thats what causing his semen to smell bad? please help. I don't want to this to be the reason for a break up. I've taken a shower and its still there. even when I go to use the bathroom I smell it. he is not circumcised and doesn't shake after he urinates. It's actually annoying that he doesn't do that, I've even pointed it out to him. It's sad men aren't in tune with their own body.