We have known for a long time that smoking during pregnancy exposes the child to risks (miscarriages, premature babies, delayed development of the newborn, etc.). What we didn't know was that smoking during pregnancy changes the DNA of the fetus. An international study, published in the American Journal of Human Genetics, explains that a link has been established between smoking in pregnant women and health problems in their child. Smoking while pregnant would therefore be the cause of chemical modifications of the fetal DNA.
As part of an international study, researchers have succeeded in identifying new genes, linked to child development, affected by tobacco. Changes similar to those seen in adult smokers. Since the fetus is not directly exposed to cigarette smoke, many of the effects are transmitted through the placenta.
The study, carried out on more than 6,600 women and their children worldwide, is one of the largest ever. The researchers nevertheless took care to distinguish “persistent” smokers (who smoked daily during pregnancy) from “occasional” smokers. In total, non-smokers would represent 62% of the women studied, against 25% of "occasional" smokers and 13% of "persistent".
To be able to carry out their project, the scientists took a blood sample from the umbilical cord after the child was born. The result ? For babies whose mothers were in the category of "persistent smokers", 6073 places in their DNA were found to be modified. You should know that about half of the DNA is altered by smoking. Thus the genes involved in the development of the lungs, the nervous system and cancers are affected. There is also evidence that smoking during pregnancy can cause abnormalities such as cleft lip.
However, the study does not specify the effects of electronic cigarettes on the fetus.