Objective: The aims of this study were to compare clinical characteristics and outcome of neo nates with congenital myotonic dystrophy (CMD) according to the number of cytosine, thymine, guanine (CTG) copies and to analyze the relating factors for survival. Methods: The patients were divided into two groups; less than or equal to 1,000 CTG copies (group A) and above 1,000 CTG copies (group B). This study compared the maternal CTG copies, obstetric characteristics, and patients' clinical characteristics, morbidity, hospital course, and long term outcome between group A and B, and also analyzed the relating factors for survival.
Results:The twentythree patients were confirmed by gene analysis in the neonatal period. Nine patients (39.1%) were included in group A and fourteen patients (60.9%) in group B. There was no correlation between the number of CTG copies of the mothers and their babies. There were no significant differences in maternal obstetric characteristics, patient's clinical findings, morbidities, hospital course and mortality between group A and B. Seven patients died before discharge and six patients among 16 who survived died after discharge. Analyzing the relating factors for survival, Apgar score at 1 and 5 minute were significantly higher in patients who survived than those who expired (P=0.0001, P=0.01, respectively). All survived patients showed developmental delay and 7 patients (58.3%) failed to thrive. Conclusion: There was no correlation between the number of CTG copies of the mothers and their babies. There were no statistical differences in maternal obstetric characteristics, patient's clinical findings, morbidities, hospital course, and mortality between the two groups. Apgar score at 1 minute and 5 minute were the relating factors for survival.