This actually hadn't occurred to me before.
We had the first set today simply because I had 3 other children off on school holidays and couldn't face baby howling along with 3 concerned siblings either fighting over him or howling too.
Anyway after i'd had the eyes rolled at me for wanting to breast feed him during the procedure to lessen the pain which they didn't allow incase he inhaled the milk and choked (which i couldn't think of a counter argument to that so agreed reluctantly but if anyone can for the next one i'd be grateful), he had the injections and went bloody nuts.
So whilst he's screaming and I'm trying to clam him down (and the nurse is continuously trying to take him off me for a cuddle, yeah like he want to go to a stranger who's just jabbed him over his mother), she says of course because he's that bit older he can have more calpol, the poor little 8 week olds only get one 2.5ml, he at 12 weeks can have two 5ml does.
So that for me seems another reason to delay.