Growth factors and metabolic markers in cord blood: relationship to birth weight and length.

Low birth weight and length for gestational age are associated with a high risk of short stature and metabolic syndrome in adulthood. The mechanisms that link prenatal growth to adult stature and metabolic syndrome have not yet been entirely clarified. The aim of our study was to evaluate the relationship between standardized anthropometric measures at birth and insulin-like growth factor (IGF)-I, IGF-II, insulin, adiponectin, and non-esterified fatty acid (NEFA) cord blood levels in the general population. One hundred fifty-eight random newborn subjects (77F, 81M) from Genoa, Italy, were analyzed. Anthropometric parameters were measured and standardized according to standard Italian tables. Insulin values were treated as categorical, since in several cases the results fell below detection cut-off. Mean birth weight was 3,214.23∓488.99 gr and mean length was 49.82∓2.17 cm. Females had higher mean IGF-I (p=0.04), and were more likely to have insulin values either <2 μU/ml or >4.5μU/ml (p= 0.04) compared to males. Weight and length SD scores (SDS) were higher in subjects with elevated insulin levels (p=0.002). A moderate correlation was found between weight and IGF-II (r=0.354). Multivariable analysis demonstrated that standardized birth weight was associated with IGFII and insulin values. Our data highlight the importance of IGF-II in fetal growth and suggest that gender differences should be taken into consideration when evaluating prenatal growth.