Cord insulin and C-peptide--distribution in an unselected population.

Objective: To assess the distribution of cord blood insulin in an unselected population, and examine its relation to birthweight centiles.
Setting: District General Hospital in Nottinghamshire.
Subjects: 209 unselected singleton births.
Mean Outcome Measure: Cord blood insulin; cord blood C-peptide; birthweight centiles.
Results: Hyperinsulinaemic babies (greater than 97th centile for cord insulin) were found at all birthweight centiles. 15% of high birthweight babies were hyperinsulinaemic. For low birthweight babies, the distribution of cord insulin/C-peptide was skewed indicating a high number of low values. Hypoinsulinaemic babies were present up to the 50th centile for birthweight.
Conclusions: Abnormalities of fetal insulinisation may be found in babies of all birthweights.