Adiponectin concentration in umbilical cord serum is positively associated with the weight ratio of fetus to placenta.

Context: Adiponectin (APN) concentration in umbilical cord serum is higher than that in adult serum. Except for the positive association between birth weight and cord APN concentration, little is known about the pathophysiological function of APN in fetal development.

Objective: The objective of this study was to evaluate the relationship of cord serum APN and IGF-I concentrations with the development of the fetoplacental unit.

Design And Methods: Umbilical cord serum APN and IGF-I concentrations were measured in term singleton deliveries (n = 94). The association of cord APN and IGF-I concentrations was evaluated in relation to fetal weight, placental weight, and fetoplacental (F/P) weight ratio.

Results: Mean concentrations and sd of APN and IGF-I were 36.1 +/- 14.0 microg/ml and 58.6 +/- 27.0 ng/ml, respectively. Cord APN concentration was positively associated with F/P weight ratio (r = 0.375, P < 0.001) as well as fetal weight (r = 0.389, P < 0.001) but not placental weight. Cord IGF-I concentration was positively associated with fetal weight (r = 0.405, P < 0.001) and placental weight (r = 0.400, P < 0.001) but not F/P weight ratio. In multiregression analysis, only APN concentration resulted in a significant determinant of F/P weight ratio among variables (beta = 0.376, P < 0.001).

Conclusions: In cord hyperadiponectinemia, fetuses tend to be disproportionately larger for their placental weight and vice versa in cord hypoadiponectinemia. APN is shown to be the first biomarker positively associated with F/P weight ratio.