Maternal exposure to magnetic fields during pregnancy increases the risk of asthma in offspring


Dr Olle Johannson alerted us to this research. He says:

I have warned about this for years and years. Our own studies, both in EHS and in healthy volunteers clearly points in this direction. And further mechanistic details are nowadays abundant, see e.g. Johansson O, "Disturbance of the immune system by electromagnetic fields — A potentially underlying cause for cellular damage and tissue repair reduction which could lead to disease and impairment", Pathophysiology 2009; 16: 157-177.

The fact that I now can not continue these investigations is a true scandal. I just wonder what the fathers and mothers of asthmatic young children think - and will think - about this situation...?! Will they be as happy as my opponents?

Maternal Exposure to Magnetic Fields During Pregnancy in Relation to the Risk of Asthma in Offspring
De-Kun Li, MD, PhD; Hong Chen, MPH; Roxana Odouli, MSPH

Arch Pediatr Adolesc Med. Published online August 1, 2011. doi:10.1001/archpediatrics.2011.135

Objective: To determine whether maternal exposure to high levels of magnetic fields (MFs) during pregnancy is associated with the risk of asthma in offspring.

Design: A prospective cohort study.

Setting: Kaiser Permanente Northern California.

Participants: Pregnant Kaiser Permanente Northern California members in the San Francisco area.

Main Outcome: Measures Asthma was clinically diagnosed among 626 children who were followed up for as long as 13 years. All participants carried a meter to measure their MF levels during pregnancy.

Results: After adjustment for potential confounders, a statistically significant linear dose-response relationship was observed between increasing maternal median daily MF exposure level in pregnancy and an increased risk of asthma in offspring: every 1-mG increase of maternal MF level during pregnancy was associated with a 15% increased rate of asthma in offspring (adjusted hazard ratio [aHR], 1.15; 95% confidence interval [CI], 1.04-1.27).

Using the categorical MF level, the results showed a similar dose-response relationship: compared with the children whose mothers had a low MF level (median 24-hour MF level, 0.3 mG) during pregnancy, children whose mothers had a high MF level (>2.0 mG) had more than a 3.5-fold increased rate of asthma (aHR, 3.52; 95% CI, 1.68-7.35), while children whose mothers had a medium MF level (>0.3-2.0 mG) had a 74% increased rate of asthma (aHR, 1.74; 95% CI, 0.93-3.25).

A statistically significant synergistic interaction was observed between the MF effect and a maternal history of asthma and birth order (firstborn).

Conclusion: Our findings provide new epidemiological evidence that high maternal MF levels in pregnancy may increase the risk of asthma in offspring.

Author Affiliations: Division of Research, Kaiser Foundation Research Institute, Kaiser Permanente, Oakland, California.

Click here for the full paper.

Click here for more research on the health effects of EMFs.


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