I know - lucky for him, I remembered my SOH today (has been away several times recently). I'll be having the last laugh on this one though - knowing what I was like after DD, he's in for another 'dry spell'...
As one of my mates said - definition of first time pg is checking the date of your last period to sort out your dates. Definition of subsequent pg's is knowing EXACTLY the date you got pg on & being able to remember whose birthday it was....