How do I ask my dad for birth control...awkward?

my dad is a doctor(emergency doc) and he is a modern medical doctor unlike my mom his ex-wife and holistic nutritionist. I need to go on birth control, not or the birth control, just for my hormones. my boobs shrink and grow drastically and my period can last up to 3months. I am fifteen and it has been 4 years since I started my period, so it should be more regular and not o random. anyways...my mom a holistic doc thinks birth control will kill me. (I think it's bs) but my dad is not against birth control. how o I ask him. please help? thanks