Smoking grandmothers increase the risk of autism in female grandchildren

Researchers are studying the effects of grandmothers smoking on their grandchildren
It is generally known that smoking is unhealthy and can cause health problems. Researchers have now found that grandmothers smoking during pregnancy massively increase the risk that their female grandchildren will later develop autism.

Researchers at the University of Bristol found in their study that grandmothers smoking during pregnancy have a significant impact on the likelihood that their female grandchildren will one day develop autism. The physicians published the results of their study in the scientific journal "Scientific Reports".

When mothers smoke during pregnancy, it not only endangers their children's health, but also the health of their grandchildren. Physicians found that if the grandmother smoked during pregnancy, thereby greatly increasing the risk of developing autism in female grandchildren. (Image: highwaystarz / fotolia.com)

Researchers analyze the data of 14,500 subjects
For their study, the experts examined the data of 14,500 people. They found that smoking grandmothers can have disastrous consequences for female grandchildren. Later, when the grandmothers smoked during pregnancy, female grandchildren were 67 percent more likely to have poor social communication skills and repetitive behaviors. In addition, the risk of autism increased by 53 percent, explain the authors of the study.

Men are more likely to suffer from autism than women
The incidence of autism has increased in recent years. Some experts attribute this increase to an improved diagnosis. However, the researchers in the current study believe that environmental impacts such as smoking during pregnancy may also play a major role. About one in 100 people suffers from autism, more men are affected than women.

Grandmother smoking increases the risk of autism only in female grandchildren
However, the negative impact of smoking on the likelihood of autism was only apparent in girls. Scientists suspect that smoking can damage the so-called mitochondrial DNA, which is only passed on to the female lineage.

Be sure to protect your little kids from tobacco smoke
We already know that protecting a baby from tobacco smoke is essential to give your baby a healthy start in life, emphasizes author Jean Golding.

Why is there a link between smoking and autism?
There are two possibilities with regard to the underlying mechanisms. There are DNA damages that are transmitted to the grandchildren. Or there is an adaptive response to smoking that makes the grandchild more susceptible to autism, adds author Marcus Pembrey.

Increased risk of autism only in the second generation?
The initial mitochondrial DNA mutations often have no open-label effect in the first generation, but the effects may increase if they are transmitted to the offspring, the experts explain.

Why is cigarette smoke so harmful?
Cigarette smoke contains more than 4,000 chemicals, including cyanide, lead and at least 60 cancer causing compounds. However, it is mostly nicotine and carbon monoxide that are responsible for the complications associated with smoking during pregnancy, the researchers explain.

Effects of smoking
Nicotine throttles the baby's oxygen by narrowing the blood vessels throughout the mother's body, including those in the umbilical cord, the experts say. Red blood cells transport oxygen in humans. By smoking, these molecules start to absorb carbon monoxide. This aggravates the problem in addition, report the doctors. Smoking during pregnancy has been shown to cause stillbirth, premature birth, low birth weight, and a variety of developmental problems. (As)