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[A review of epidemiologic studies on ultrasound during pregnancy].

This article reviews most of the more recent epidemiological studies on the effectiveness and possible risks of conventional sonography. With the help of such a review, case reports, very often cited out of context, can be better evaluated. Publications which have attempted to study the number of malformations, diagnosable by ultrasound, and to the effect of ultrasound on postnatal mortality and morbidity are scrutinized. Furthermore the question of possible late effects of ultrasound is addressed, such as effects on birth weight, neural development and cancer incidence. Routine sonography is of great value; no negative late effects on the child have been found. The effectiveness and risks of Doppler flow ultrasound have not been studied sufficiently well to allow a similar conclusion.