Should I inform DH that we are TTC?

My husband and I have been married for 2 years and have a 6 month old son that we both love. I would love to have another one and kind of get our 2 kids done with while we are young and can handle sleepless nights and our jobs but my husband refuses because he says we need to wsit a few years so it is not too much at one time. I have started TTC and he knows that we have not been on any kind of BC since my pregnancy. Should I come clean and tell him what I am doing or let it be. I mean its not like he does not know that no BC and sex everyday usually end in a pregnancy.