Routine ultrasound screening in pregnancy and the children's subsequent handedness

Objective: To study a possible association between ultrasound screening in early pregnancy and altered cerebral dominance measured by the prevalence of non-right handedness among children, particularly boys. Methods: Follow-up of 8 to 9 year old children to women who participated in a randomised controlled trial on ultrasound screening during pregnancy in 1985-87. The children were followed up through a questionnaire sent to their mothers. The dominant hand of the child was assessed by eleven questions. The dominant foot by one question. Results: No differences were found in non-right handedness between children in the screening and non-screening group. In separate analyses on ultrasound exposure and non-right handedness among boys a significant difference was found (odds ratio 1.33; 95% confidence interval 1.02-1.74). Conclusion: This study could not rule out a possible association between non-right handedness among boys and ultrasound exposure in early fetal life. The association was, however, confined to analyses comparing exposed and non-exposed boys and no associations were found when the comparisons were performed according to the randomised groups. (C) 1998 Elsevier Science Ireland Ltd.