Fetal loss from umbilical cord abnormalities--a difficult case for prevention.

The summaries of 12 pregnancies in which fetal distress and death were thought to be the result of umbilical cord abnormalities are presented. These included six cases of stricture and torsion of the cord, one case of umbilical vein aneurysm, one case of perivascular haemorrhage near the fetal end of the cord, one case of umbilical vein thrombosis, two cases of true knot of the cord and one case of very short cord. The perinatal mortality was 75% in the whole group (9 out of 12 fetuses), there being eight stillbirths and one neonatal death. Of the 12 fetuses, only three were small for dates at delivery. Nine patients volunteered the history of a decrease in fetal movements, and non-stress cardiotocography (NST) was abnormal in eight patients. It was noted, however, that fetal death tended to occur rapidly after an abnormal test. Observations in our series indicated that antepartum fetal deaths due to umbilical cord abnormalities are still difficult to prevent, as it is often impossible to detect fetal distress in time for appropriate intervention. Prompt action to deliver the baby after an abnormal NST appears to be a necessary step to prevent antepartum deaths due to such causes.