Repeated measures of urinary oxidative stress biomarkers during pregnancy and preterm birth.

Abstract

OBJECTIVE:

The purpose of this study was to investigate oxidative stress as a mechanism of preterm birth in human subjects; we examined associations between urinary biomarkers of oxidative stress that were measured at multiple time points during pregnancy and preterm birth.

STUDY DESIGN:

This nested case-control study included 130 mothers who delivered preterm and 352 mothers who delivered term who were originally recruited as part of an ongoing prospective birth cohort at Brigham and Women's Hospital. Two biomarkers that included 8-hydroxydeoxyguanosine (8-OHdG) and 8-isoprostane were measured in urine samples that were collected at up to 4 time points (median 10, 18, 26, and 35 weeks) during gestation.

RESULTS:

Urinary concentrations of 8-isoprostane and 8-OHdG decreased and increased, respectively, as pregnancy progressed. Average levels of 8-isoprostane across pregnancy were associated with increased odds of spontaneous preterm birth (adjusted odds ratio, 6.25; 95% confidence interval, 2.86-13.7), and associations were strongest with levels measured later in pregnancy. Average levels of 8-OHdG were protective against overall preterm birth (adjusted odds ratio, 0.19; 95% confidence interval, 0.10-0.34), and there were no apparent differences in the protective effect in cases of spontaneous preterm birth compared with cases of placental origin. Odds ratios for overall preterm birth were more protective in association with urinary 8-OHdG concentrations that were measured early in pregnancy.

CONCLUSION:

Maternal oxidative stress may be an important contributor to preterm birth, regardless of subtype and timing of exposure during pregnancy. The 2 biomarkers that were measured in the present study had opposite associations with preterm birth; an improved understanding of what each represents may help to identify more precisely important mechanisms in the pathway to preterm birth.

• Authors: Kelly K Ferguson, Thomas F McElrath, Yin-Hsiu Chen, Rita Loch-Caruso, Bhramar Mukherjee, John D Meeker
• Journal: American journal of obstetrics and gynecology (Am J Obstet Gynecol) Vol. 212 Issue 2 Pg. 208.e1-8 (Feb 2015) ISSN: 1097-6868 [Electronic] United States
• PMID: 25111586 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical References

• Biomarkers
• 8-epi-prostaglandin F2alpha
• 8-Hydroxy-2'-Deoxyguanosine
• Dinoprost
• Deoxyguanosine

Topics

• 8-Hydroxy-2'-Deoxyguanosine
• Adult
• Biomarkers (urine)
• Case-Control Studies
• Deoxyguanosine (analogs & derivatives, urine)
• Dinoprost (analogs & derivatives, urine)
• Female
• Humans
• Infant, Newborn
• Longitudinal Studies
• Male
• Odds Ratio
• Oxidative Stress
• Pregnancy
• Premature Birth (urine)
• Prospective Studies