Clue - the ACS site cited above says “Full-term infants born to women who smoke weigh approximately 7 ounces less than those born to non-smokers.”
That 7-ounces is your clue that they made this stuff up. If the birth weight was presented as women who are smokers will have a baby whose birthweight is X percentage lower than if they didn’t smoke, that might mean something.
One baby might weigh 7 ounces less than another baby for any number of reasons – that’s what babies weigh in that family, the mother is a tiny Asian woman, the mother is a crackhead, the mother is 13. Hmmm. Do you think that Asians, crackhead, and the kind of 13-year olds who get pregnant might also be the type who are, statistically, likely to smoke? I’m not disputing the low-birth weight link for women who smoke, I’m pointing out that this bullet list is done in BS style.
We know about low birth weight because, women who were basically like other women except for their nicotine habit had babies with lower birth weights. (Although it’s possible this is because, in general, they ate less, it is still the case that the end result is smaller baby, at greater risk if something goes wrong.) This is how science works. Look at what science has to say about the second-hand smoke claims.
Oh, I don’t mean to be snitty. I’m not angry at you. I’m mad at people who will make up crap because they can’t trust people to think (that is, people who truly want people to take better care of themselves, but feel they must use hysterical exaggerations to achieve that) and people who are up to no good (lawyers).