A woman's smoking habit during pregnancy can have a negative impact on her grandchildren's health.
Exposure to tobacco in the womb has been known to increase the risks of wheezing and asthma in children. For the child's safety, women are recommended to avoid smoking after conceiving. However, according to new research, a grandmother's smoking habit can put even her grandchildren at higher risks of asthma.
Dr. John S. Torday, and Virender K. Rehan, from the Los Angeles Biomedical Research Institute, based their findings on two previous studies.
Of the two studies, the first one is an experiment conducted by Dr. Rehan on pregnant rats. The rats were exposed to nicotine during pregnancy. Dr. Rehan and his team found exposure to nicotine leading to epigenetic changes in pregnant women, putting multiple generations at the risk of many respiratory conditions, including asthma.
The second one is the Children's Health Study from Southern California. Irrespective of the fact whether a mother smoked or not, grandmaternal smoking was found directly linked to increased risk of asthma in children.
Based on the two studies, researchers found environmental factors in pregnancy playing a prominent role in determining the well-being of subsequent generations of the family. Epigenetic modification caused by environmental factors affects lung cells and sex cells, increasing the risks of an abnormal development of lungs, the researchers said, while explaining the occurrence.
"These studies break new ground in validating and further explaining the mechanisms involved in the transmission of epigenetic human diseases," Dr. Torday said in a news release. "The transmission of the asthma to the second generation and its prevention by a specifically-targeted molecular intervention are the first unequivocal demonstrations of multi-generational transmission of an epigenetically-mediated effect on the offspring."
Apart from asthma, smoking during pregnancy brings many health problems for the child. Premature birth, low birth weight, cot death, infections, still birth and autism are some of the risks. However, nearly 14 percent of women in the country continue smoking, even after the confirmation of pregnancy.
"Asthma is the most common chronic disease of childhood, resulting in a significant impact on the lives of children and driving up medical costs for all," Dr. Rehan said. "While many factors contribute to asthma, smoking during pregnancy is a well-established one and one that can be avoided. Eliminating smoking during pregnancy would significantly reduce the prevalence of childhood asthma for this generation and for future generations."
The study has been published in the Review of Obstetrics & Gynecology.
