is being prone to miscarriages hereditary?

Eliza
I got a Bfp on two pregnancy tests and I told my dad tonight. He seemed to be apprehensive about my being pregnant and said that he didn't even know how many miscarriages my mom had, and that it was so common that it wasn't even a big deal to him. Really made me feel like I'm going to miscarry. I am 5 w 6 days since LMP. I tried to say that a high percentage of miscarriages happen before the woman even knows she's pregnant, but he presumed to tell me that most miscarriages happen at 9-10 weeks. Is this true? He really freaked me out and now I'm worried about miscarrying. I can't argue with him because he's a doctor and insists he knows what he's talking about. Advice? I'm worried because I'm almost six weeks and still have very few symptoms. My breasts aren't sore, I only feel fatigued and have some back/muscle pain. I'm still trying to wrap my head around being pregnant and I'm not sure I quite trust the pregnancy tests yet.