thoughts on a serangt mother?

I've been trying to years to have a baby. I'm depressed, desperate and angry. Words can't explain how depressed I am. I CAN get pregnant but I always loose them at around 4months. Doctors haven't given a reason why.

My husband & I have been married 4yrs. & things are good but you know when you're ready and it just doesn't happen? It feels like we are missing something already. We are dying for our little family already.

& it feels even worse when everyone around us is having babies left an right. I get the question all the time. I'm already pushing 30, I feel incomplete. But my dream is to be a mother. And I want to have my own but may have to except the fact that I can't. 😢💔💔💔💔💔

What do you think about a serangant mother? How does that even work? Can you pick someone?