Can't decide on another baby

I want one more baby, partner says we can think about trying in five years time but I'm 37! If I stay with him and wait the five years and I have left it too late and can no longer concieve I will end up resenting him, equally if birth control fails I feel he will end up resenting me(our first child was conceived while I had an iud, second was planned). I think he's said this to appease me knowing I will be too old to have kids by then but I can't really argue as hes said yes in the future...