Are doctors guessing 🤔

I know miscarriages happen a lot more than we realize,but when I had my first miscarriage the doctor said oh the chances of you having another one is low because most women don’t have them back to back ... 10 months later I just had my second miscarriage so I let my body heal and continued my prenatal vitamins! And yet this happened again !!! I’m so angry,hurt,worried,Sad and wondering what will happen when I get pregnant next time .. I have two older kids already and I’m like what happened between then and now besides my age ! I hate that one day I’m fine and then one day I’m not ! The experience gets more traumatic with each pregnancy 🤰🏾 I don’t know what to do at this point it’s like why take the vitamins when like my doctor said she’s seen healthy have a hard time ttc and she’s seen drug addicts have healthy pregnancies and they never put in any work like I have preparing my body ! Sorry for this rant but I’m having a moment right now