Lipid peroxidation in cord blood: the effects of umbilical nuchal cord.

OBJECTIVE

To examine the relation between cord entanglement around the fetal neck and umbilical arterial measures of free oxygen radical activity at birth.

DESIGN

Prospective observational study of the lipid peroxide levels in umbilical cord arterial blood.

SETTING

Delivery suite of Prince of Wales Hospital, Hong Kong.

POPULATION

Women with a singleton pregnancy, at term (37 to 42 weeks of gestation), cephalic presentation, spontaneous or induced labour and an initially normal fetal heart rate tracing.

METHODS

A series of 230 singleton deliveries had determination of two lipoperoxides in umbilical arterial cord blood: malondialdehyde and organic hydroperoxide. Umbilical pH, PO2, PCO2 and base excess were also measured in both umbilical cord arterial and venous blood.

MAIN OUTCOME MEASURES

Umbilical cord blood gases and arterial malondialdehyde and organic hydroperoxide levels.

RESULTS

Forty-nine cases of nuchal cord were observed: 14 tight and 35 loose. Tight nuchal cord was associated with a low 1-min Apgar score and increased lipid peroxide levels. Loose nuchal cord was associated with larger amniotic fluid volume and significantly decreased lipid peroxide levels.

CONCLUSIONS

This study suggests that tight nuchal cord is associated with increased free oxygen radical activity in the fetus, but that loose nuchal cord carries no adverse effects.