Trying for the first time

I was young when I had my daughter I was 17-18. I’m 25 years old now.. my hubby and I are trying to have another one. My question is: on here for today it said 27% for having a baby. How true is that? It’s my first time really trying like I said. I had all the signs for ovulation so I know I’m good on that. We just BD as well.