Limb reduction defects in fetuses with homozygous α-thalassaemia-1

Limb reduction defect is a rare event. Its exact pathogenesis is unknown. We retrospectively reviewed the outcome of 130 fetuses affected by homozygous α‐thalassaemia‐1 and found that 11 of them (8 per cent; 95 per cent confidence interval: 4–13 per cent) had terminal transverse limb reduction defects. Chromosome study was available in ten fetuses with limb defects and the results were normal. We postulate that the strong association between homozygous α‐thalassaemia‐1 and limb reduction is related to the hypoxic insult in early gestation. This may be the final common pathway in the pathogenesis of other forms of limb reduction defects. © 1997 John Wiley & Sons, Ltd.