Different degrees of fetal oxidative stress in elective and emergent cesarean section.
BACKGROUND
Several studies have addressed the influence of labor and mode of delivery on oxidative stress. Still it is unclear whether oxidative stress is related to delivery itself or whether it reflects a pre-existing fetal oxidative status.


OBJECTIVE
To investigate whether the degree of fetal oxidative stress is different between distressed fetuses that were delivered by emergent cesarean section and non-distressed fetuses that were delivered by elective cesarean section.


METHODS
The protocol of this prospective study was approved by the Institutional Review Board Committee. Amniotic fluid and umbilical artery blood were prospectively collected from 21 parturients who were delivered by an emergent cesarean section for non-reassuring fetal heart rate pattern and from 21 parturients who were delivered by an elective cesarean section in a tertiary care center. Oxidative stress was evaluated in amniotic fluid, umbilical cord plasma and erythrocytes by determining malondialdehyde concentration and glutathione peroxidase (GPX) activity.


RESULTS
Malondialdehyde concentration was higher in amniotic fluid (mean +/- SEM) (2.2 +/- 0.7 nmol/l vs. 0.6 +/- 0.02 nmol/l, p < 0.05), in umbilical cord plasma (1.2 +/- 0.2 nmol/l vs. 0.7 +/- 0.3 nmol/l, p < 0.05) and in umbilical cord erythrocytes (159.6 +/- 48.6 nmol/g Hb vs. 85.8 +/- 5.2 nmol/g Hb, p < 0.05) in women delivering by emergent cesarean compared to those delivering by elective cesarean. GPX activity was enhanced in amniotic fluid (12.4 +/- 2.2 U/l vs. 5.1 +/- 0.6 U/l, p < 0.05) and GPX activity/hemoglobin ratio was higher in cord blood (22.0 +/- 0.8 U/g Hb vs. 18.7 +/- 0.9 U/g Hb, p < 0.05) in women delivering by emergent cesarean compared to those delivering by elective cesarean.


CONCLUSIONS
Distressed fetuses delivered by emergency cesarean exhibited increased malondialdehyde concentrations, an indicative parameter for oxidative damage, and enhanced GPX activity an antioxidant enzyme, in amniotic fluid and umbilical cord blood compared to non-distressed fetuses delivered by elective cesarean section. This is probably an indication of higher fetal oxidative stress.
Lurie
Samuel
S
Department of Obstetrics and Gynecology, Edith Wolfson Medical Center, Holon, Israel. lurie@nashim.net
Matas
Zippora
Z
Boaz
Mona
M
Fux
Asora
A
Golan
Abraham
A
Sadan
Oscar
O
D000328:Adult; D000653:Amniotic Fluid / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D002585:Cesarean Section; D004638:Emergency Treatment; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D005316:Fetal Distress / Q000378:metabolism* / Q000503:physiopathology; D005979:Glutathione Peroxidase / Q000378:metabolism; D006340:Heart Rate, Fetal / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress; D011247:Pregnancy; D011248:Pregnancy Complications / Q000601:surgery*; D011446:Prospective Studies
D015415:Biomarkers; D008315:Malondialdehyde; D005979:Glutathione Peroxidase