Antenatal Ultrasound and Risk of Autism Spectrum Disorders

Environmental Health Investigations Branch, California Department of Public Health, Richmond, CA 94804, USA.
Journal of Autism and Developmental Disorders (Impact Factor: 3.06). 10/2009; 40(2):238-45. DOI: 10.1007/s10803-009-0859-4
Source: PubMed

ABSTRACT We evaluated antenatal ultrasound (U/S) exposure as a risk factor for autism spectrum disorders (ASD), comparing affected singleton children and control children born 1995-1999 and enrolled in the Kaiser Permanente health care system. Among children with ASD (n = 362) and controls (n = 393), 13% had no antenatal exposure to U/S examinations; case-control differences in number of exposures during the entire gestation or by trimester were small and not statistically significant. In analyses adjusted for covariates, cases were generally similar to controls with regard to the number of U/S scans throughout gestation and during each trimester. This study indicates that antenatal U/S is unlikely to increase the risk of ASD, although studies examining ASD subgroups remain to be conducted.

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Available from: Sherian X Li, Jan 16, 2015
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    • "91). Just as Ziskin and Petitti have suggested, such assumptions are still present today which continue to falsely impress upon the science that safety studies have been adequate and thorough (for example, see [16]). Research into transient cavitational and thermal effectors have been considerable, and provided A. "
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    ABSTRACT: Science has shown that risk of cavitation and hyperthermia following prenatal ultrasound exposure is relatively negligible provided intensity, frequency, duration of exposure, and total numbers of exposures are safely limited. However, noncavitational mechanisms have been poorly studied and occur within what are currently considered “safe” levels of exposure. To date, the teratogenic capacity of noncavitational effectors are largely unknown, although studies have shown that different forms of ultrasound-induced hydraulic forces and pressures can alter membrane fluidity, proliferation, and expression of inflammatory and repair markers. Loose regulations, poor end user training, and unreliable ultrasound equipment may also increase the likelihood of cavitation and hyperthermia during prenatal exposure with prolonged durations and increased intensities. The literature suggests a need for tighter regulations on the use of ultrasound and further studies into its teratogenicity.
    03/2013; 4(1):81-87. DOI:10.2478/s13380-013-0112-7
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    • "ASD cannot be reliably diagnosed until after birth, and thus prospective investigations of prenatal life have been rare. One study retrospectively compared the frequency and timing of prenatal ultrasound scans among children later diagnosed with ASD and matched typically developing controls, reporting largely null findings (Grether et al. 2010). However, information on the type of ultrasonography the women received could not be gleaned from medical records in approximately 25 % of scans, and therefore only limited conclusions can be drawn from these data. "
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    Journal of Autism and Developmental Disorders 03/2012; 42(12). DOI:10.1007/s10803-012-1526-8 · 3.06 Impact Factor
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