It's really not necessary anymore to "prove" that smoking during pregnancy is just plain bad.
Granted, it's an addiction that is extremely hard to quit but excuses like "my doctor said it would be worse for the baby if I quit due to my stress" are simply that. Excuses.
And no doctor I know has ever said that nor believed it. The best thing a smoking pregnant woman can do is quit.
We know that smoking around newborns has been linked to respiratory problems and even SIDS.
Children born to smoking mothers can go into withdrawal themselves and are prone to being of a lighter weight than is healthy, as well having suppressed immune systems.
Previous studies have shown that smoking parents may exacerbate asthma.
But a new study from the Karolinska Institutet in Stockholm has shown that the babies of pregnant smokers may be directly affected in terms of their asthma risks, rather than from second hand smoke itself.
While no absolute proof is available, this study, according to the reporting Reuter's article "had a large enough group of kids who were exposed to smoking in the womb, but not after birth, according to the researchers.
"And it found that those children were two-thirds more likely to have asthma by age six, versus kids whose moms did not smoke during pregnancy. Even smoking during the first trimester alone was linked to higher asthma risk." (healthnews.com)
Over 21,000 children in Europe were involved in this study and overall, 7 percent had an asthma diagnosis by the time they were 5 years old.
The study ultimately showed that "just under seven percent of all children in the study had been diagnosed with asthma by the time they were four to six years old. And the risk, [researcher] Bergstrom's team found, was higher when mothers had smoked during pregnancy. Those children were 65 percent more likely to develop asthma, when factors like birth weight and both parents' own history of asthma were taken into account."
Another smaller study recounted by EmpowHER, was conducted in the United States and had similar findings.