Minor congenital anomalies and ataxic cerebral palsy.

The incidence of minor congenital anomalies was examined in 36 patients with ataxic cerebral palsy, in unaffected family members, and in 100 unrelated control subjects. None of the control subjects or family members had more than four anomalies, and 25 of 36 (69%) of the patients had more than four. The distribution of anomalies differed considerably, with 60% of the index cases having seven or more, and 94% of the controls having three or less. The number occurring in the patients was significantly more than in their relatives. Of the 25 patients with more than four anomalies, 16 (64%) had undergone potentially adverse perinatal or early postnatal events. Thus minor congenital anomalies were considerably more frequent in those with ataxic cerebral palsy than in related or unrelated control subjects. These anomalies may be markers of early prenatal factors that contributed to the adverse outcome either directly or by predisposing to perinatal difficulties.