Multiple vascular profiles in the umbilical cord; an indication of maternal smoking habits and intrauterine distress.

A total of 644 umbilical cords were examined over a period of 5 years, 40 cords (6.2 per cent) showed more than the normal three vascular profiles on cross-section. Both the umbilical arteries and vein showed multiple profiles, although arterial profiles were far more commonly multiple. Clinical data were correlated with the histological findings. Heavy smoking was significantly associated with multiple vascular profiles. Maternal age and rhesus group were not significantly related however, but there was some association with primiparity. Fetuses with a gestational age between 33 and 38 weeks were significantly more likely to have multiple vessels than either fetuses beyond 38 weeks or less than 33 weeks gestation. Multiple channels also occurred significantly more frequently in still birth than in live birth cords. We suggest that multiple vascular profiles represent a response to intrauterine hypoxia. Inflammation of the cord was associated with multiple channels and suggests linkage between these two indications of fetal distress.