If you mean FTM then I'm a little confused and am not even going to address the birth control question. I'm sort of confused about the birth control game you want to play in general, but I wanted to respond to say that if your potential partner is a transguy, unless they've said they prefer she/her or they/their pronouns, you should be using he/his.  
   
 I think it's also a little kinder to phrase things like "My potential submissive is transgender (FTM)" or something like that. I know it sounds super picky, but describing someone as "a transgender" is....I don't know it just comes off wrong. As if the person is defined solely by their gender identity. I know what you meant and I don't at all think it was meant in a malicious way, but there's just something about it that feels off. Hopefully some of the trans ladies on these boards will chime in about that as a cisgender person schooling another cisgender person about trans semantics is almost as backward.  
   
 As with all things sex, and especially all things BDSM, the best person to ask about this is your partner. If you can't have honest conversations about your fantasies/play then they aren't the right person for you.