Diagnostic significance of malondialdehyde level and catalase activity evaluation in women with preterm labor

Objective. To determine diagnostic significance of combined evaluation of malondialdehyde level and catalase activity in the blood of pregnant women with threat and/or onset of preterm labor. Subject and methods. The study involved 112 women 18 to 40 years old. Group I - 36 pregnant women with delivery between 22 to 36 weeks of gestation and within 7days after the examination. Group II included 42 women with threatened preterm labor and subsequent delivery at term. Group III - 34 generally healthy pregnant women delivered at term. Spectrophotometric method was used to measure level of malondialdehyde (MDA) as a marker of lipid peroxidation and catalase enzymatic activity in maternal peripheral blood. Results. It was shown that the enzymatic activity of catalase in plasma of women with realized preterm labor and women with threatedpreterm delivery with subsequent pregnancy retention was increased in comparison to control group. The same time at 28-32 weeks of gestation the quantity of women with catalase activity higher than 150 U/ ml was significantly higher in group of women with threated preterm delivery with subsequent pregnancy retention then in early delivered women. The concentration of MDA in plasma of women with realized preterm labor at 22-27 weeks of gestation was significantly higher in comparison with control group. At term of 28-32 weeks the same tendency was observed but the difference was not significant. No significant difference in MDA level was observed between women with threated preterm delivery and subsequent delivery at term and control group. Conclusion. The main finding of the study is that in pregnant women there are some systemic compensatory reactions intended to decrease the level of reactive oxygen species production by catalase in the situation of threated preliminary labor. Catalase activity reduction in the blood of pregnant women with realized preliminary labor can indicate the disturbances in reactive oxygen species production system as a result of mother and placenta adaptive resources attenuation. Thus, elevated level of MDA at 22-27 weeks of gestation and decreased activity of catalase at 28-32 weeks of gestation may be negative prognostic factors in the case of preterm labor threat.

preterm labor, oxidative stress, malondialdehyde, catalase