Hi -- New Here. Question about Prometrium

So I'm 4-and-some weeks along and made my first ob/gyne appointment.  Without even knowing what my existing levels are, they want to right away put me on prometrium.  According to the nurse it doesn't hurt to have more progesterone.  Um, I don't believe that -- quick aside -- my friend had weekly progesterone shots to maintain her pregnancy because she miscarried years ago, they never checked her levels, and oh, whaddayaknow, her baby boy now has a hooked penis which she found out after the fact is caused by too much progesterone.

I actually did have all my hormones balanced before we even started trying with my natural doctor, but she doesn't do ob/gyne stuff.  I'm just curious how you guys tried to keep things on the natural/minimal intervention side with a mainstream ob/gyne, if that is at all possible. 

Thanks!