Getting married and not having children of your own is a condition no one prays for because it can be very frustrating and sometimes it might feel like you have been forsaken by God.
This is a short prayer you can say:
Gracious father, the word of God which contains your promises says in Romans 8:32 that “He who did not spare his son, but gave him up for us all- how will he not also, along with him, graciously give us all things.”
This scripture assures me of your love for me, and I believe that if you can give up on your own for my sake, then you will also give me a child of my own, I pray and believe that you will keep your word, Amen.