Objective: A descriptive study was conducted to investigate the epidemiological characteristics of oblique facial clefts in China.
Methods: From 1987 to 1992, data were collected from more than 500 hospital-based units involved in a monitoring program and were analyzed by the National Center for Birth Defects Monitoring. The monitored subjects were the hospitalized births from 28 weeks gestation to a period within 7 days after delivery.
Results: There were 71 cases of oblique facial clefts in 4,489,692 births with an incidence of 0.16/10(4) in China. The incidence of oblique facial clefts in the rural and urban areas were 0.19/10(4) and 0.14/10(4) respectively, 0.18/10(4) in males and 0.12/10(4) in females. No significant differences were found. The unilateral oblique facial clefts were counted for 80%, and bilateral cases 20%. The incidence of unilateral oblique facial clefts in males is higher than that in females. The perinatal mortality was as high as 51%. There are 76% cases with associated abnormalities, most of which involved the maxillofacial region. The most common associated abnormality is cleft lip with cleft palate.
Conclusion: The incidence of oblique facial clefts in China is the same as those in other countries. There is an unilateral predominance in this defect, especially in males. The perinatal mortality of this defect is high.