Lipid peroxidation in cord blood: the effect of amniotic fluid volume.

OBJECTIVE

To assess the effect of amniotic fluid volume on umbilical cord arterial lipid peroxide levels in relation to intrapartum events.

DESIGN

Prospective observational study.

SETTING

Delivery suite of a teaching hospital, the Chinese University of Hong Kong.

POPULATION

Women with singleton, term, cephalic presentation, and an initially normal fetal heart rate tracing.

METHODS

All pregnancies had amniotic fluid index assessments before and after amniotomy and cord arterial lipid peroxide determination at delivery. Multiple regression analysis.

MAIN OUTCOME MEASURES

Cord arterial malondialdehyde and organic hydroperoxide levels.

RESULTS

In 247 cases following amniotomy levels were inversely correlated with intrapartum amniotic fluid index. Amniotic fluid index during labour was an independent determinant of cord arterial lipid peroxide concentration, along with duration of second stage, absence of epidural, presence of tight nuchal cord entanglement and evidence of fetal distress.

CONCLUSIONS

Oligohydramnios during labour is associated with high levels of lipid peroxidation in the fetus, reflecting an increase in hypoxic cellular damage by free radicals.