Introduction: At present, about 1% of newborns are delivered through assisted reproductive technologies (ART) worldwide. This study aimed to evaluate and compare the growth parameters of children born in assisted and natural conception at 5 years of age. Materials and Methods: In a cross-sectional case control study, weight, height and head circumference of 5-year old children were assessed. The case group consisted of term, singleton babies who were products of ART in the Center for Infertility of Shahid Sadoughi University, Yazd, Iran in 2005. The control group consisted of term, first child, singleton and spontaneously conceived 5-year-old children who were referred for vaccination to primary health care center of Shahid Akbari in 2010. Results: Fifty-eight girls (47.5%) and 64 boys (52.5%) “with equal numbers in each of the 2 groups” were evaluated. Sex distribution, mean ages of fathers and mothers were not statistically significant different in both groups. Children born after ART tend to have lower birth weight, smaller birth head circumference and lower weight at 5 years of age. Having low birth weight (<2500 g), being underweight and having short stature at the age of 5 were more common in babies born through ART. Conclusion: Growth retardation is more prevalent in babies born through ART. Thus, growth assessment, parents’ knowledge about child physical development, and timely and accurate follow-up of these children are necessary for early detection of any growth disorders. Key words: ART, Growth, Height, Natural Conception, Weight

Introduction. Exposure to high intensity noise produced by MRI is a cause for concern. This study was conducted to determine the temporary and permanent effects of exposure to noise created by performing MRI on the hearing threshold of the subjects using conventional and extended high frequency audiometry. Methods. This semiexperimental study was performed on 35 patients referred to Shahid Rahnemoun Hospital for head and neck MRI due to different clinical conditions. The hearing threshold of patients was measured before, immediately after, and 24 hours after performing 1.5 Tesla MRI using conventional and extended high frequency audiometry. SPSS version 18 was used to compare the mean hearing thresholds before and after MRI using paired T test and repeated measures analysis. Results. Comparison of auditory thresholds in conventional and extended high frequencies before and immediately after MRI showed a significant shift at 4 KHz (P = 0.008 and P = 0.08 for right and left ears), 6 KHz (P = 0.03 and P = 0.01 for right and left ears), and 14 KHz (P =0.03 and P = 0.31 for right and left ears). However, there was no significant difference between audiometric thresholds before and 24 hours after MRI. Conclusion. Noise due to 1.5 Tesla MRI can only cause transient threshold shift.