Apnea and its possible relationship to immunization in ex-premature infants.

This study compared the characteristics of infants hospitalized with apnea that participated in a vaccine trial compared with two control groups which consisted of 100 infants randomly selected from the same vaccine trial and 52 consecutively born very low birth weight (VLBW) infants. A total of 23 infants were admitted with apnea of whom 19 weighed <1500 g at birth and all were born at <37 weeks gestation. More of the VLBW infants in the apnea group had neonatal neurological complications compared with the VLBW control group (p=0.005). Ten of 11 children with apnea within 72 h of immunization were possibly related to vaccination.