Amniotic fluid transforming growth factor-beta1 and the risk for the development of neonatal bronchopulmonary dysplasia.

Chorioamnionitis (CAM) can initiate fetal lung injury resulting in neonatal bronchopulmonary dysplasia (BPD). While neonates with BPD have higher amniotic fluid concentrations of proinflammatory cytokines, overexpression of transforming growth factor (TGF)-beta(1) also appears important in the pathogenesis of BPD. The aim of this study was to investigate the relationship between TGF-beta(1) and CAM-induced fetal lung injury. Forty-four amniotic fluid samples were obtained at delivery of preterm infants (median gestation, 28 weeks; birth weight, 908 g). TGF-beta(1) and interleukin (IL)-6 concentrations in the amniotic fluid were measured with ELISA. Both TGF-beta(1) and IL-6 concentrations in the amniotic fluid increased with increasing histological severity of CAM (each p < 0.0001). The presence of both BPD and histological CAM was associated with significantly higher amniotic fluid TGF-beta(1) and IL-6 concentrations than the presence of BPD without histological CAM, or the absence of both (each p < 0.0001). Both concentrations also correlated with the duration of oxygen administration in the neonates (each p < 0.0001). Amniotic fluid TGF-beta(1) seems to be important in CAM-induced fetal lung injury progressing to neonatal BPD.