Activity of the enzyme delta-aminolevulinate dehydratase and parameters of oxidative stress in different modes of delivery.

<bold>Aims: </bold>The objective of this study was to investigate the effect of the type of delivery (vaginal and cesarean) on the activity of the enzyme delta-aminolevulinate dehydratase (δ-ALA-D), which as yet has not been studied, and the markers of oxidative stress.<bold>Methods: </bold>Seventy-six mothers and their newborns were divided into two groups: normal birth (VD) and elective cesarean section (ECS). Samples of maternal and umbilical cord blood were collected up to 5 min after birth. Thiobarbituric acid reactive substances (TBARS), advanced oxidation protein products (AOPP), protein thiol (P-SH), nonprotein (NP-SH), the ferric reducing ability of plasma (FRAP), total antioxidant capacity (TAC), catalase, and δ-ALA-D enzyme activity were tested.<bold>Results: </bold>TBARS and AOPP were significantly higher in mothers of the VD group, while P-SH, NP-SH, FRAP and TAC were reduced. In newborns, TBARS and AOPP did not differ between the groups; however, in the VD group, there was a decrease in P-SH, NP-SH, FRAP, TAC, and catalase. The activity of the δ-ALA-D enzyme was decreased in mothers and neonates born by VD.<bold>Conclusions: </bold>Mothers undergoing VD had higher levels of free radicals and lower antioxidant defenses, while their newborns decreased antioxidant defenses likely to contain the oxidative imbalance. The inhibition of the δ-ALA-D enzyme in this scenario allows its use as a useful marker of oxidative stress in different obstetric settings. [ABSTRACT FROM AUTHOR]