Do pregnant mothers who smoke cigarettes affect the baby?

It isn't like you're out of the woods once you get that plus sign on the pregnancy test. The stakes get even higher then. Smoking pregnant can boost the risk of miscarriage, and can negatively effect fetal development, such as slowing the baby's growth rate. In addition, writes John Martin for Fertility Neighborhood, smoking pregnant can cause blood vessels in the uterus and placenta to narrow, and can negatively affect the blood pressure and heart rate of both the mother and developing fetus.

"Smoking pregnant … causes considerable damage to the fetus and to the infant during the initial growth phase," said Knut-Olaf Haustein, MD, with the Institute for Nicotine Research and Smoking. "A smoking mother puts her child at considerable risk, not only of higher incidence of miscarriage, premature ablatio placentae (premature separation of the placenta from the uterine wall prior to delivery), and reduced weight at birth, but also of deformities." source: http://www.conceivingconcepts.com/learning/articles/smoking.html