Need advice (no hate)

I’m 17 years old and I was previously in a relationship where I got pregnant. After being about two months pregnant I had a miscarriage. I had already bought my baby lots of things and had to return them all. It was really hard on me and has been ever since. The relationship I was in while I was pregnant was bad and I got out of it and I’ve been with a new guy for almost 9 months now and he was there for me when I lost my baby. He’s 17 too. Ever since the baby died I’ve been really lost. I know we are young but he knows how empty I feel without a baby. I’ve told him many times I will he lost until I have one again. I’m just not happy in life. There’s a empty hole in my heart. I feel like I can’t be in a relationship and be happy until I fill that whole in my heart. He’s told me he wants to have kids one day but I’m losing myself. I want a baby now. He’s about to graduate from high school and turn 18. How do I tell him I want to try for a baby?