A series of 106 consecutive ductal closures in premature infants was reviewed to assess the incidence of left vocal cord paralysis. To our knowledge, this syndrome is described for the first time in premature infants. In our experience, it is a relatively benign complication that completely resolves clinically in several weeks. This complication occurred in 5.2% of patients closed by suture ligature and in none of those closed by a surgical clip. Although the series is too small for this difference to be statistically significant, we believe it strongly favors the use of the clip, with less dissection.