I don’t know what to do

Husband and I have been trying to conceive for 9 months now, and in those 9 months we’ve had 4 months that were positive tests. I have had 4 chemical pregnancies. It seems I can get pregnant pretty easily, but I just can’t hold on to them. My doctor refuses to do any testing until we’ve been trying for a year, but I’m getting SO frustrated because what’s the point?! If I do get pregnant in the next 3 months I’m just going to lose those too! Why put someone through continuously trying and the ache of loss when 4 chemical pregnancies is a pretty good indicator that something isn’t right.