Recurrent Miscarriage after 1 healthy Birth

I am 23 years old, I have had 3 pregnancies, my first had zero complications and a healthy little girl was born full term. The 2nd and 3rd were both miscarriages one at 8 weeks one at 6 weeks with 2 years in between with no pregnancy at all. I am not on birth control nor have my husband and I used any preventative measures. In fact we are TRYING to conceive. My question is could there be something wrong with me that is preventing pregnancy/causing miscarriages? My OB has yet to run any test or even mention that something may be wrong but with my first pregnancy, I got pregnant within a month of trying and now it has taken years of trying to conceive only to lose the fetus early on. I do not know what is causing this and any advise would be very helpful. thank you.