A recent study has found that maternal exposure to magnetic fields during pregnancy increases the child’s risk of developing asthma.  Every 1-mG increase of maternal MF level during pregnancy was associated with a 15% increased rate of asthma in offspring.

“Children born to mothers who had a median daily MF exposure during pregnancy between 0.3 milligauss (mG) and 2 mG had a 74% increased risk of asthma.  Children born to mothers who had a median daily EMF exposure during pregnancy over a 2 mG EMF had a 3.5-fold increased risk (a 350% increased risk) of asthma.”

“This study shows a statistically significant increased risk for asthma.  Every 1 mG increase of maternal EMF level was associated with a 15% increased risk of asthma in the child. 1.15; 95% confidence interval [CI], 1.04- 1.27).  A dose-response is shown for increasing maternal MF during pregnancy and asthma in the off-spring.” – Cindy Sage

Asthma has become the top cause of hospitalization and emergency room visits for US children.  Affecting about 13% of children, it is the most common chronic illness suffered by children under the age of 18 in the United States.

Magnetic field exposure has long been known to be associated with childhood leukemia.

ABSTRACT

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.

Download PDF of Full Paper

Read Comments on Maternal Exposure to Magnetic Fields During Pregnancy Posted on EMF Safety Network by Cindy Sage

Read Article on WebMD

Please support our work by making
a tax-deductible donation.
We are 100% donation-based
and need your support
to educate, communicate and analyze
critical developments in this field.
Thanks so much for your help! Please give
generously. We depend on you.