Rezk AY, Abdulqawi K, Mustafa RM, Abo El-Azm TM, Al-Inany H. (2008). Fetal and neonatal responses following maternal exposure to mobile phones. Saudi Med J. 29(2):218-223.
The potential health effects of exposure to radiofrequency fields emitted by mobile phones are poorly understood. It is uncertain if electromagnetic fields (EMFs) emitted from mobile phones at non-thermal levels elicit a biological response in cells or tissues. EMF’s have been associated with several disorders, including depression and memory loss, as well as with neurological, degenerative, and heart diseases. They have also been shown to influence embryonic mortality and development in chickens.
The objective of this study was to study fetal and neonatal heart rate and cardiac output following acute maternal exposure to EMF emitted by mobile phones.
The study participants included 90 healthy pregnant women aged 18-33 years and 30 healthy newborn infants. The study was conducted at a hospital in Cairo, Egypt between October 2003 and March 2004. Four groups of 30 participants were formed: pregnant women with gestational age 25-30 weeks (Group I), pregnant women with gestational age 31-35 weeks (Group II), pregnant women with gestational age 36-40 weeks (Group III), and male and female newborns of these 90 women (Group IV). In the first three groups, women were placed in a semi-recumbent position and a belt measuring fetal cardiac function was placed around their abdomen. Fetal heart rate and fetal cardiac output were measured for 10 minutes to establish baseline measurements. Women then held a mobile phone on dialing mode on the right side of their head in a typical phone position for 10 minutes while fetal heart rate and fetal cardiac output were measured. In group IV, newborns were sedated and mothers held a mobile phone on dialing mode on the right side of their own heads while the infants’ heart rate and cardiac output were measured.
In all groups, there was a statistically significant increase in heart rate and decrease in cardiac output after maternal mobile phone use. The percent increase in heart rate decreased as gestational age increased. The percent increase in heart rate was 13%, 7%, 6%, and 4% in groups I, II, III, and IV respectively. Similarly, percent decrease in cardiac output went from 27% in group I to 21% in group II to 13% in group III and to 11% in group IV.
Interpretation and Limitations
Use of mobile phones during pregnancy has been associated with headaches, sleep irregularity, hematological, and cardiovascular abnormalities. In this study, EMFs appeared to reduce the ability of the fetus’ or neonate’s heart to contract, which has also been found in rats. This effect could be caused by direct toxicity of the EMF to the cardiac muscle, by a disruption of normal red blood cell function, or by disrupting normal calcium channel function. Another study of the effects of EMFs on heart rate found conflicting results, though their methods were slightly different. An effect of EMF on heart rate is biologically plausible and may be mediated through the central nervous system. Nonetheless, the results in this study may be a nonspecific physiological response to the magnetic fields.
Prenatal and postnatal exposure of mothers to EMFs emitted by mobile phones may influence cardiac function in fetus’ and in infants.