I don't know if I can take another...

My wife and I went in to see my midwife and found out I miscarried. This is our 3rd one since we started TTC. I'm starting to feel at a loss. My midwife is nor finding any reason for the miscarriages and my body seems 100% ready to carry a baby but every time we get pregnant it doesn't carry to term. I don't know what to do anymore...