Maternal Exposure to Ionizing and Non-Ionizing Radiations during Pregnancy with Low Birth Weight in 1200 Newborns: A 15 Month Study

Document Type : Original Article


1 Professor of Medical Physics, Center for Radiological Research, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran

2 Assistant Professor of Medical Physics, Center for Radiological Research, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran


Introduction: Low birth weight is the 2nd leading cause of mortality in infants. Since there are controversies in the effect of ionizing radiation of the mother on the birth weight of newborn so we tried to eliminate the effect of confounding factors observed in other studies, to assess the effect of dental radiographies in pregnant women on the risk of delivery of low birth weight infant.
Methods: All mothers with their first term labor (vaginal or caesarean) between 2006-2008 (1385-1387; according to Iranian Calendar) whose newborns had been registered in the neonates’ screening program in Shiraz were interviewed and surveyed. and based on mothers’ history and dental or non-dental (head and neck) radiography, 1200 newborns were divided into two groups in a cohort study. First group consisted of the newborns whose mothers had dental radiography and second group consisted of those whose mothers had no dental radiography. All interfering variables such as exposure to non-ionizing radiations were controlled. The obtained findings were analyzed, using proper statistical tests as student’s t-test and chi square and ANOVA.
Results: Among them, only 19 mothers (1.58%) had been exposed to dental radiography.The mean weight of the newborns whose mothers had been exposed to ionizing radiation in dental radiographies was 2988.95 + 424.8 grams and that of the newborns with non-radiographed mothers was 3113.00 + 511.240. The difference between the means was not statistically significant. Furthermore, the difference between the mean weight of the newborns with mothers who had non-dental radiographies and those not exposed to any radiation during the pregnancy period was not statistically significant.
Conclusion: This study found no clear relationship between dental radiography during pregnancy and birth weight. Due to the low frequency of dental radiography during pregnancy, it is necessary to do more long-term studies to investigate this phenomenon more accurately.


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