Stop using ultrasound to determine sex of fetuses, urge doctors, radiologists
“Canada’s pregnancy specialists and the nation’s radiologists are calling for a halt on using ultrasound for the sole purpose of determining the sex of an unborn fetus.
In a new joint policy statement, the Society of Obstetricians and Gynaecologists of Canada and the Canadian Association of Radiologists also say it could be considered unethical for private, commercial clinics to offer “entertainment” ultrasounds purely for the purpose of creating “keepsake” videos for expectant parents.
The position statement comes amid mounting concerns that in Canada, people are using ultrasound to determine the sex of a fetus early in pregnancy and to have it aborted if it is a girl.”
Nature Reviews Neuroscience 11, 490-502 (July 2010) | doi:10.1038/nrn2851
Behavioural phenotyping assays for mouse models of autism
Jill L. Silverman, Mu Yang, Catherine Lord & Jacqueline N. Crawley
Autism is a heterogeneous neurodevelopmental disorder of unknown aetiology that affects 1 in 100–150 individuals. Diagnosis is based on three categories of behavioural criteria: abnormal social interactions, communication deficits and repetitive behaviours. Strong evidence for a genetic basis has prompted the development of mouse models with targeted mutations in candidate genes for autism. As the diagnostic criteria for autism are behavioural, phenotyping these mouse models requires behavioural assays with high relevance to each category of the diagnostic symptoms. Behavioural neuroscientists are generating a comprehensive set of assays for social interaction, communication and repetitive behaviours to test hypotheses about the causes of austism. Robust phenotypes in mouse models hold great promise as translational tools for discovering effective treatments for components of autism spectrum disorders.
Mice Exposed to Diagnostic Ultrasound In Utero Are Less Social and More Active in Social Situations Relative to Controls.
McClintic AM, King BH, Webb SJ, Mourad PD.
Department Neurological Surgery, University of Washington, Seattle, Washington.
Clinical use of diagnostic ultrasound imaging during pregnancy has a long history of safety and diagnostic utility, as supported by numerous human case reports and epidemiological studies. However, there exist in vivo studies linking large but clinically relevant doses of ultrasound applied to mouse fetuses in utero to altered learning, memory, and neuroanatomy of those mice. Also, there exists a well-documented significant increase in the likelihood of non-right-handedness in boys exposed to diagnostic ultrasound in utero, potentially relevant given the increased prevalence of autism in males, and reports of excess non-right-handedness in this population. Motivated by these observations, we applied 30 minutes of diagnostic ultrasound to pregnant mice at embryonic day 14.5 and assayed the social behavior of their male pups 3 weeks after their birth. The ultrasound-exposed pups were significantly (P < 0.01) less interested in social interaction than sham-exposed pups in a three-chamber sociability test. In addition, they demonstrated significantly (P < 0.05) more activity relative to the sham-exposed pups, but only in the presence of an unfamiliar mouse. These results suggest that fetal exposure to diagnostic ultrasound applied in utero can alter typical social behaviors in young mice that may be relevant for autism. There exist meaningful differences between the exposure of diagnostic ultrasound to mice versus humans that require further exploration before this work can usefully inform clinical practice. Future work should address these differences as well as clarify the extent, mechanisms, and functional effects of diagnostic ultrasound's interaction with the developing brain. Autism Res 2013, ●●: ●●-●●. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.
*Note: Mouse models of autism rely on studying symptoms, and are infantile. http://www.nature.com/nrn/journal/v11/n7/full/nrn2851.html
A survey in 2006 found that only 3.8% of sonographers could correctly explain the safety readout on an ultrasound machine. This is unacceptable.
Watch this video to learn more about shortcomings in sonographer education worldwide. This is important if you plan on having children any time soon.
This video is a review of what science currently understands about the safety of prenatal ultrasonography.
The short version: medicine does not yet fully understand how ultrasound affects the body, and there has been little research into it. When a practitioner tells you that sonography is perfectly harmless/completely safe, that is not backed by scientific evidence.
Considering that almost every woman in the world gets an ultrasound (or more) during pregnancy, this is unacceptable.
Transvaginal ultrasound is when a sonographer inserts an ultrasound transducer into a woman’s vagina for internal imaging. They can detect a variety of conditions, including but not limiting to cancers or other growths, fluid deposits, bone damage, . . . it is useful for many valid diagnostic reasons.
There are, however, some risks associated with having the transducer closer to the fetus: One study detected damage in microvilli extracted from fetuses exposed to transabdominal ultrasound, but not transvaginal for the same duration: http://www.ncbi.nlm.nih.gov/pubmed/11776185
[Influence of sonographic examination on embryo villi during early pregnancy].
To evaluate the effects of sonographic examination on embryo villi during early pregnancy.
Eighty early pregnant women intended for artificial abortion were divided into 4 groups: group I served as control, the remaining 3 groups underwent pelvic sonographic examination transabdominally for 10 minutes (group II), transvaginally for 3 minutes (group III) or for 10 minutes (group IV) respectively. After 1 hour embryo villi were obtained through artificial abortion and examined by electronic microscopy, biochemical methods and sister chromatid exchanges (SCE).
In group IV, but not group II, III, the embryo microvilli were found broken, lost and disarranged. The rough endoplasmic reticulum of trophoblasts expanded. Their malondial dehyde levels increased while the superoxide dismutase (SOD) decreased as compared with control (P < 0.01). There was no difference of SCE among these 4 groups.
It is recommended that sonographic examination should be done through abdominal approach for shorter than 10 minutes during early stage of pregnancy.
I thought this correlation was concerning. While the ultrasound hearing study dismisses that ultrasound can cause damage to hearing as though it were nothing big, perhaps the improved hearing in infants is a red flag that ultrasound could be promoting auditory hypersensitivity.
This would not have to be a big thing — ASD is a gradient, right? So, children who were near threshhold would be tipped over, while it may possibly help infants with worse hearing. There’s two sides to every coin, and every tool can harm or heal.
For individuals with autism spectrum disorder or ‘ASD’ the ability to accurately process and interpret auditory information is often difficult. Here we review behavioural, neurophysiological and imaging literature pertaining to this field with the aim of providing a comprehensive account of auditory processing in ASD, and thus an effective tool to aid further research. Literature was sourced from peer-reviewed journals published over the last two decades which best represent research conducted in these areas. Findings show substantial evidence for atypical processing of auditory information in ASD at behavioural and neural levels. Abnormalities are diverse, ranging from atypical perception of various low-level perceptual features (i.e. pitch, loudness) to processing of more complex auditory information such as prosody. Trends across studies suggest auditory processing impairments in ASD are most likely to present during processing of complex auditory information and are more severe for speech than for non-speech stimuli. The interpretation of these findings with respect to various cognitive accounts of ASD is discussed and suggestions offered for further research.
Prenatal ultrasound exams have become increasingly frequent. Although no serious adverse effects are known, the public health implications would be enormous should adverse effects on auditory development be shown. This study looks to establish a possible correlation between hearing loss and increased prenatal ultrasound exposure.
Our results show that there is no correlation between a higher level of prenatal ultrasound exposure and hearing loss. Indeed, infants who had more prenatal ultrasounds in the third trimester were more likely to pass their screening hearing exams. The finding that children receiving more prenatal ultrasounds have a higher likelihood of passing newborn hearing screens serves as an excellent reminder of the classic statistics rule that correlation does not imply causation.