does age make it hard to get pregnant?

Hello, i am 25 years old and my husband is 58. At first, i honestly didnt think it was okay to be with someone older, way older. But we have been together for 4 years, and they have been great. i love him so much but now im wanting babies. We are currently trying and its not working out so well. i been keeping track of my periods and keeping up with when im ovulating but that doesnt seem to work aswell... so what should i do??? please help! please help!!!