my hubby is kinda the same, originally he wanted to just 'let it happen' and he presumed when my belly started to grow ie 3-4 months along, we would 'realise' we were pg. bless him.
i had to explain to him about time of ovulation (at first he really hated bding just 'to make babies') but i explained that is how it is done now, we time it and he had better be ready to perform when is say so

