Hi im 28 been ttc for a year and 4 months

Lauren • i just got my BFP
I was on the IUD for 5 years been off of it for a year and 5 months and still nothing I've been taking prenatal vitamins for 3 months now thinking it will help me and my fiance thinks something is wrong I've been to my dr's and they took my blood and everything was find but my iron I don't know what to do please help ty