First-trimester increase in oxidative stress and risk of small-for-gestational-age fetus.
OBJECTIVE
Investigation of increased oxidative stress in early pregnancy and association with an increased risk of small-for-gestational-age (SGA) fetus.


METHODS
Longitudinal case-control study.


METHODS
University Hospitals of Leicester NHS Trust, Leicester, UK.


METHODS
Low-risk pregnant women with no current or pre-existing medical illness were recruited at a large teaching hospital from 2004 to 2006.


METHODS
Recruitment performed at the time of the dating ultrasound scan (12+/-2 weeks of gestation). Spot urine samples collected at 12+/-2 and 28+/-2 weeks of gestation were analysed for 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) by liquid chromatography with tandem mass spectrometry). SGA was defined as birthweight <10th centile based on customised centile calculator (www.gestation.net). This identified the cases (n=55), whereas controls (n=55) were mothers whose babies were appropriate for gestational age (AGA, birthweight 10th-90th centile). Statistical analysis was performed using GraphPad Prism v.5. The relationship between maternal urinary 8-oxodG at different gestations and customised SGA was investigated by nonparametric tests.


METHODS
Customised SGA and AGA pregnancies.


RESULTS
Urinary 8-oxodG concentrations were significantly increased in pregnancies with subsequent SGA compared with concentrations in normal pregnancies; 12 weeks: 2.8 (interquartile range [IQR] 1.96-3.67) versus 2.2 (IQR 1.26-3.28) pmol 8-oxodG/micromol creatinine (P=0.0007); 28 weeks: 2.21 (IQR 1.67-3.14) versus 1.68 (IQR 1.16-2.82) pmol 8-oxodG/micromol creatinine (P<0.0002). Concentrations decreased significantly between week 12 and 28 (P=0.04 and P=0.02 for controls and cases).


CONCLUSIONS
In this study, urinary 8-oxodG at 12 and 28 weeks were elevated in SGA compared with AGA pregnancies. This may reflect early placental changes predating clinical features of SGA.
Potdar
N
N
Reproductive Sciences Section, Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, UK. saphaire_neelam@yahoo.com
Singh
R
R
Mistry
V
V
Evans
M D
MD
Farmer
P B
PB
Konje
J C
JC
Cooke
M S
MS
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000032:analysis / Q000652:urine; D001724:Birth Weight; D016022:Case-Control Studies; D003367:Cotinine / Q000032:analysis; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000652:urine; D005260:Female; D005317:Fetal Growth Retardation / Q000209:etiology* / Q000378:metabolism; D005500:Follow-Up Studies; D006801:Humans; D018384:Oxidative Stress; D011247:Pregnancy / Q000652:urine*; D011261:Pregnancy Trimester, First / Q000652:urine; D011262:Pregnancy Trimester, Second / Q000652:urine; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods; D012463:Saliva / Q000737:chemistry; D012907:Smoking / Q000009:adverse effects; D018709:Statistics, Nonparametric
D015415:Biomarkers; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine; D003367:Cotinine