Ooh I dunno. An old colleague had a friend who smoked throughout her pregnancy and her baby was incredibly grumpy and hard to settle and we speculated that maybe it was nicotine withdrawal. However, I failed to give up smoking entirely when I was pregnant (and yes I am horribly ashamed and guilty) and DS was about the easiest baby in the world, easily settled, very content. So who knows. Maybe for some, not for others.
Clearly smoking more than 4000 chemicals in every stick and letting that filter through to your babies bloodstream, is going to have a damaging effect. Babies born to heroin takers are born addicts and withdraw immediately and seeing a newborn jumping around in a cot because of this has to be one of the worst sights in the world. Therefore, a baby will be suffering from nicotine withdrawal and whatever the selfish, defensive smoking mother denies, deep down she knows it's bad for the baby. End of.
my sil's both smoked thru their pregancies and all 3 kids have various chest infections i smoked before i knew i was pregnant found out at four weeks and never smoked again until i was 36 weeks pg as i freaked out about having a c section and didnt smoke again til i had given up bfing when she was 10 months then the pull got too much
and all there kids slept thru from an early age and where 'good' but poorly kids
but my lo didnt sleep thru til she was 12 mo but was a very healthy happy child so who knows