A prospective study was conducted in the Otorhinolaryngology department, National University Hospital, Singapore to evaluate the effects of mid-trimester amniocentesis on the auditory system in preschool children of about four years of age. Fifty-nine children whose mothers had mid-second trimester amniocentesis and 63 children (control group) whose mothers did not have amniocentesis in that pregnancy were recruited. The children were subjected to audiological tests to assess hearing impedance abnormalities. The incidence of prematurity, neonatal admissions, ear and respiratory infections, auditory function, speech and language development in children were evaluated because these factors have a bearing on the development of auditory impedance abnormalities. There was no significant increase in the neonatal admission rates, impairment of speech and language development and auditory function in children whose mothers had mid-second trimester amniocentesis compared with the control group whose mothers did not have amniocentesis. An incidental finding in this study was an increased incidence of respiratory illnesses in the children in the amniocentesis group (57.6%) compared with the control group (30.1%). This needs further evaluation with a properly designed study.