Asymmetric crying facies and congenital anomalies.

Asymmetric crying facies and congenital anomalies. The frequency of hypoplasia of the depressor anguli oris muscle in a newborn population was 41 in 6360 (1 in 155). No adverse factors were noted in the obstetric background of affected infants and the pathogenesis of the lesion is not clear. The incidence of associated congenital anomalies detected in the newborn period was 2 in 41 (4. 9%). The lesion was predominantly left-sided (83%) in this series, which contrasts with the side of the lesion in infants found in hospital populations (32%). Even allowing for the anticipated increase in incidence of other anomalies during follow-up, the prognosis appears to be more favourable than that indicated by studying series of infants ascertained by way of associated anomalies.