Falls from high bridges

To the Editor: A leading articleI and special review' published recently in the Journal focus on male-mediated causes of birth defects, with special reference to herbicide exposure. Both articles correctly maintain that male-mediated teratogenesis, particularly from herbicides, is unlikely. Unfortunately, the authors neglected to cite two major studieson this topic, both, incidentally, conducted in Australasia. The first study was a large, independent investigation of the offspring of Australian Vietnam veterans.' This study identified 8517 children with birth defects born in 34 hospitals between 1966 and 1979. These infants were matched with normal infants born in the same hospital, as nearlyas possible simultaneously, to a mother of similar age to the mother of the child with the anomaly. The fathersof all subjects and controls were identified and checked against a list of all men who served in the Australian army between 1962 and 1972 (70 000 Australians served in Vietnam). The fathers identified as havingserved in the Army during this period were then classified according to whether or not they had served in Vietnam. The epidemiologists who carried out this study say that the sample was large enough to enable the study to meet its aims. One hundred and twenty seven of the fathersof childrenwithcongenital anomalies and 123 of the fathers of healthy children were Vietnam veterans. A comparison of individual defects showed no increase in anencephaly, limb defects or cleft palate among the childrenof Vietnamveterans. All of these conditions have been anecdotally linked to a father's military service in Vietnam. The second study, conducted in New Zealand, examined the handlers of 2,4,5-T. J. C. Lane, SmithStreet. Camberwell, Vic. 3124.