There is only one thing is you do and have to do - influence,
change and compromise. 
This is a tricky issue, ok but first, let take a look marriage on
fundemental level. Marriage is between two, for ill or for good,
both sticking to each other and growing from it spiritually,
emotionally and physically. Love is often in the picture (though
not neccessary) and probably a willing and planned thing (again,
not neccessary).
Since marriage is between two - having kids or not is not exactly
neccessary PROVIDED if both couples have the same mentality. If
this preception/viewpoint is clashed - something has to be worked
out.
Having kids is great element into the marriage - it brings growth
and development to the marriage as well as happiness (though not
neccessary, but a child reasonably brought up (personal
definition), every parent would feel gald and satisfied.
I suspect there could be other reasons on why he doesn't want kids.
Seek and slowly advance into his inner world - you people are only
the first year of your relationship. Take your time and concern to
understand why is this happening.
Personal experience? Childhood psychology past?
External factors? When you have a better picture of this: probably
you can repost you question and we can do a better analysis over
this.
P.S (Negative scenario): If there is absolutely nothing that is
affecting him over a long course of trying to seek the root of the
problem. Either he doesn't want to tell OR he could hold weak faith
in the relationship. (Family/immediate family influence?) because
having kids is a burden IF things like divorce, etc were to take
place. But I wouldn't guess things here and complicate your
thinking. Take care lady. Repost once you have a better picture
yourself too. Remember take time to know his heart and inner
thoughts.
Cheers
