Research looks at early exposure to mobile phone risk

By Dr. Ananya Mandal, MDDec 9 2010

There has been plenty of speculation that mobile phones are not good for pregnant mums but a new study sheds light on the actual connection. It finds that pregnant women who regularly use mobile phones may be more likely to have children with behavioral problems, particularly if their children start using mobile phones in their first seven years. American researchers said that the risk of behavioral problems rose by 30% if such exposure was present. Those exposed before birth and in early childhood were at 50% higher risk than those who were not exposed they said.

The findings, published in the Journal of Epidemiology and Community Health, were based on a study of 28,000 seven-year-olds and their mothers, who were part of the Danish National Birth Cohort study. The team from the University of Southern California enrolled 100,000 pregnant women between 1996 and 2002 and monitored their behaviour and their children’s health over eight years. Mothers were asked questions about their lifestyle, mobile phone use, breast feeding practices etc. The authors write, “Although it is premature to interpret these results as causal, we are concerned early exposure to mobile phones could carry a risk, which, if real, would be of public health concern given the widespread use of this technology.” The investigators used the variables - breastfeeding and hours spent each day with the child - as a indicator for the kind of attention mothers gave their young children. According to the study, this was partly to determine whether a mother who spent a lot of time talking on a mobile phone during pregnancy or later might be less attentive to her children - something that might also be linked to behaviour problems in her offspring.

The executive director of the Australian Centre for Radio Frequency Bioeffects Research, Rodney Croft, who is also a professor of health psychology at the University of Wollongong, was not convinced with the strength of the association however. He pointed out that there were several flaws in the study design including methodology that asked the mothers to recall phone use rather than document it in a timely manner.

In 2008 a similar study was undertaken with 13,000 children by this same team. Lead author Leeka Kheifets, an epidemiologist at the School of Public Health at the University of California at Los Angeles said that the earlier study did not factor in some potentially important variables that could have affected its results which were included in this latest study.

She said, “These new results back the previous research and reduce the likelihood that this could be a chance finding.” In the study, Kheifets and her colleagues wrote that further studies are needed to “replicate or refute” their findings.

Dr. Andrew Adesman, chief of developmental and behavioral pediatrics at the Steven and Alexandra Cohen Children's Medical Center of New York in New Hyde Park unlike Croft commended the research design. He said, “The study’s methodology was rigorous and responsible. The researchers took into account as many possible variables as they could, given the limitations of the data set.”

More than 285 million Americans no use mobile phones, according to the Cellular Telecommunications and Internet Association. Kheifets said, while there is no reason for pregnant women to avoid using their mobile phones, “precautionary measures might be warranted.” Dr. Adesman added, “The most conservative and perhaps prudent approach would be for both pregnant women and very young children to minimize their mobile phone exposure… The risks seem to be small, but nonetheless, based on this study, they’re hard to dismiss.”