Obviously, because of the thousands of chemicals in a cigarette, the ideal would be to eliminate every risk, no matter how small or theoretical, and stop smoking - and maybe in the early stages it reduces the risk of miscarriage (I don't know, but I'm sure there must be research in that area), but I know loads of people who's mothers smoked in pregnancy in the 60's and they don't appear to have suffered any detriment. My ma didn't smoke, but I still had health problems.
Luck of the draw!
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