Macrosomia revisited: ponderal index and leptin delineate subtypes of fetal overgrowth.
OBJECTIVE
We sought to reanalyze the concept of fetal macrosomia with regard to the ponderal index and to investigate the role of insulin, insulinlike growth factor I, leptin, and maternal factors on birth size in a population of infants with nondiabetic mothers.


METHODS
Venous cord blood levels of insulin, insulinlike growth factor I, insulinlike growth factor binding protein 3, and leptin were measured in 28 large-for-gestational-age and 21 appropriate-for-gestational-age newborns.


RESULTS
Large-for-gestational-age newborns can be divided into symmetric and asymmetric subtypes according to the ponderal index. Mean leptin concentrations in cord blood were significantly higher in asymmetric than in symmetric large-for-gestational-age newborns (P =.01). A positive correlation was observed between leptin and the ponderal index (r = 0.53, P =.001) and between leptin and insulin concentrations in cord blood (r = 0.53, P =.008).


CONCLUSIONS
Our results strongly suggest that macrosomia should not be classified on the basis of birth weight and gestational age alone. We also show that asymmetric macrosomic infants with nondiabetic mothers have abnormal leptin and insulin concentrations.
Lepercq
J
J
Service de Gynécologie-Obstétrique, Hôpital Saint Vincent-de- Paul, 75674 Paris Cedex 14, France.
Lahlou
N
N
Timsit
J
J
Girard
J
J
Mouzon
S H
SH
D005314:Embryonic and Fetal Development; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D005320:Fetal Macrosomia / Q000503:physiopathology*; D005865:Gestational Age; D006801:Humans; D007328:Insulin / Q000097:blood; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D020738:Leptin; D008297:Male; D011506:Proteins / Q000378:metabolism*; D014471:Umbilical Veins
D007328:Insulin; D018972:Insulin-Like Growth Factor Binding Protein 3; D020738:Leptin; D011506:Proteins; D007334:Insulin-Like Growth Factor I