Antenatal maternal corticosteroid administration and markers of oxidative stress and inflammation in umbilical cord blood from very low birth weight preterm newborn infants

Objective: To investigate the association between antenatal maternal corticosteroid administration and blood levels of reactive oxygen intermediates (ROI), reduced glutathione (GR) and interleukin-6 (IL-6) in preterm, very low birth weight infants. Methods: This was a cohort study in which cord blood samples were used for the following tests: baseline and stimulated granulocyte ROI were measured by flow cytometry; GR was assayed by spectrophotometry; and IL-6 by enzyme-linked immunosorbent assay. Two different comparative analyses of antenatal corticosteroid (betamethasone) were conducted: the first compared administration against no administration and the second compared mothers who received the complete cycle with those given only a partial antenatal corticosteroid cycle. Maternal and neonatal variables were analyzed in order to compare groups. Categorical variables were compared using the chi-square or Fischer tests, and blood marker test results were compared using the Mann-Whitney test. Results: The different corticoid therapy groups were similar in terms of all of the maternal and neonatal variables with the exception of vaginal delivery, which was significantly associated with not receiving antenatal corticosteroid. The results for ROI, GR and IL-6 did not differ when the comparison was based on simple presence or absence of administration of the steroid. However, when the complete cycle was compared against incomplete administration, median ROI and IL-6 were lower among those given the complete cycle. Conclusion: Administration of the complete cycle of betamethasone to the mother had a suppressive effect on baseline ROT and IL-6 production in very low birth weight preterm newborn infants.