Oxidative Stress in Pregnant Women Between 12 and 20 Weeks of Gestation and Preterm Birth

Abstract

Background A known relationship exists between oxidative stress and preterm birth (PTB). However, few studies have measured oxidative stress prospectively in early or midpregnancy, and no studies have used electron paramagnetic resonance (EPR) spectroscopy prospectively to predict PTB. Objective The purpose of this study was to identify predictive relationships between antioxidants and reactive oxygen species (ROS), specifically, superoxide (O2 •−), peroxynitrite (OONO−), and hydroxyl radical (●OH), using EPR spectroscopy, measured between 12 and 20 weeks of gestation and compare with the incidence of PTB. Methods Blood was obtained from pregnant women (n = 140) recruited from a tertiary perinatal center. Whole blood was analyzed directly for ROS, O2 •−, OONO−, and ●OH using EPR spectroscopy. Red blood cell lysate was used to measure antioxidants. PTB was defined as parturition at <37 weeks of gestation. Results No differences were found between ROS, O2 •−, OONO−, or ●OH with the incidence of PTB. Catalase activity, glutathione, and reduced/oxidized glutathione ratio were significantly lower with PTB. Logistic regression suggests decreased catalase activity in pregnant women is associated with increased odds of delivering prematurely. Discussion We prospectively compared antioxidants and specific ROS using EPR spectroscopy in pregnant women between 12 and 20 weeks of gestation with the incidence of PTB. Results are minimal but do suggest that antioxidants—specifically decreased catalase activity—in early pregnancy may be associated with PTB; however, these findings should be cautiously interpreted and may not have clinical significance.

The Impact of Early Pregnancy and Exposure to Tobacco Smoke on Blood Antioxidant Status and Copper, Zinc, Cadmium Concentration—A Pilot Study

“…On the other hand, higher activity of CAT could be associated with a reduced risk of many diseases during pregnancy, when exposure to tobacco smoke did not occur and that decrease in CAT activity during pregnancy in women exposed to tobacco smoke may be indicative of early-onset preeclampsia [36], which confirmed the results of a metaanalysis conducted by Wei et al [62]. In addition, lower CAT activity in early pregnancy may be related to preterm birth [63], which could be enhanced by exposure to tobacco smoke [11,64]. Probably, in our study lower CAT activity was compensated by higher activity of GPx which should be sufficient to convert H 2 O 2 to H 2 O [65], even if a higher concentration of Cu occurs.…”

Markers of Oxidative Stress in Obstetrics and Gynaecology—A Systematic Literature Review

“…The rest of the markers were researched in either one or two studies: 8-isoprostane ( n = 1), 8-OHdG ( n = 2), total peroxide ( n = 1), nitrotyrosine ( n = 1), 8-iso-prostaglandin F2α ( n = 2), 8-epiprostaglandin F2-α ( n = 1), prostaglandin F2α ( n = 1), thiol ( n = 1), disulphide ( n = 1), TOS ( n = 1), TAS ( n = 1), DNA damage in blood leukocytes ( n = 1), CAT ( n = 2), γ-glutamyl transferase ( n = 1), hs-CRP ( n = 1), GSH ( n = 1), NO ( n = 1), carbonyl proteins ( n = 1), superoxide anion expressed as reduced nitroblue tetrazolium ( n = 1), aldehyde dehydrogenase ( n = 1), GST ( n = 1), soluble fms-like tyrosine kinase-1 ( n = 1), and placental growth factor ( n = 1) [ 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 ].…”

Effect of Endogenic and Exogenic Oxidative Stress Triggers on Adverse Pregnancy Outcomes: Preeclampsia, Fetal Growth Restriction, Gestational Diabetes Mellitus and Preterm Birth

“…Another study elucidated the association between lower antioxidant levels in early pregnancy and PTB. The results suggest that while the effects of antioxidants are not that significant, a definite association exists between them, which should be cautiously interpreted prior to the clinical application of antioxidants in early pregnancy for the prevention of PTB [ 94 ]. In addition, an analysis of amniotic fluid samples collected by transabdominal amniocentesis in women with PPROM demonstrated decreased total antioxidant capacity, but no difference in oxidative stress markers regardless of whether microbial invasion or frank chorioamnionitis was present [ 95 ].…”