Adrenomedullin Concentrations in Early 2nd-Trimester Amniotic Fluid: Relation to Preterm Delivery and Fetal Growth at Birth

Abstract

Objective: The purpose of this study was to evaluate whether adrenomedullin concentrations in the early 2nd-trimester amniotic fluid predict preterm delivery or fetal growth at birth. Methods: The adrenomedullin concentrations in early 2nd-trimester amniotic fluid were measured in 70 pregnancies with term delivery and in 3 pregnancies with preterm delivery. Total and free adrenomedullin concentrations were measured from early 2nd-trimester amniotic fluid samples using an immunoradiometric assay. Results: The amniotic fluid total adrenomedullin concentrations in women with preterm delivery were significantly higher (129.7 ± 19.6 fmol/ml) than those in women with term delivery (92.5 ± 28.2 fmol/ml; p < 0.05). There were no significant differences for amniotic fluid free adrenomedullin concentrations and free/total adrenomedullin ratios between the two groups. Total or free adrenomedullin concentrations in the early 2nd-trimester amniotic fluid showed an inverse correlation both with birth weight (r = 0.27, p < 0.05, and r = 0.21, p < 0.05) and height (r = 0.30, p < 0.05, and r = 0.28, p < 0.05). There were no correlations between placental weight and total or free adrenomedullin concentrations in the early 2nd-trimester amniotic fluid. Conclusions: These results suggest that adrenomedullin concentrations in the early 2nd-trimester amniotic fluid might be related to further in utero fetal growth and that high levels of adrenomedullin in the early 2nd-trimester amniotic fluid may be involved in the occurrence of preterm delivery.