If you smoke when your pregnant what's going to happen?

What baby docs see. For a view of what doctors see before and after a baby is born, look at these answers also :) https://www.Healthtap.Com/user_questions/46059-how-will-smoking-harm-a-growing-baby.
Bad for baby. The children of women who have smoked during pregnancy are not only smaller at birth and through life, their iq's also average 10-15 points lower. This is data from a few years back but i believe it is still valid. Do yourself and baby the greatest favor, now.
Usually nothing. But do not count on it! most women smoke with little/no consequence for their fetuses, however an unlucky few will have horrendous complications that scar their families for ever. Stop as early as you can as a sacrifice for your unborn infant.