Don't think it matters too much when you see the midwife, i know they dont like seeing people before 6 weeks (as most miscarriages that happen, happen before 6 weeks) but usually they will see people between 6-10 weeks, it doesn't really matter when they do though, as it's just health history really and a few leaflets, and they need to see you at least a couple of weeks before the 12 week scan time so they have time to book you in.