Stricture of the umbilical cord

Umbilical cord stricture and overcoiling are common causes of fetal demise

Although umbilical cord stricture and umbilical cord overcoiling have been established as causes of intrauterine fetal demise, relatively few studies addressed this issue, most of them being case reports. We reviewed a total of 268 fetal autopsies during a 3-year period from 1998 to 2001. One hundred thirty nine cases of fetal demise including spontaneous abortion were identified. Nineteen percent (26 of 139) were associated with umbilical cord stricture, overcoiling, or a combination of both. Stricture of the umbilical cord was defined as a decrease in diameter in relation of the remaining umbilical cord; overcoiling as 0.3 coil/cm or greater. Fetal demise most commonly occurred in the second trimester, with a mean gestation age of 21 weeks. The average maternal age was 33 years; 15% had a prior fetal demise. We found that 77% (20 of 26) of these cases had umbilical cord stricture only or with overcoiling, 23% (6 of 26) had umbilical cord overcoiling alone. Localized deficiency of Wharton's jelly and increased collagen were found in all cases with umbilical cord stricture with or without overcoiling. In patients with umbilical cord overcoiling alone, 25% had Wharton's jelly deficiency; half of them had increased collagen deposition in the umbilical cords. The placenta was reviewed for secondary thrombosis of the vessels of the chorionic plate. Thrombosis of the vessels of the chorionic plate was noted in 54% of the patients. Our study suggests that umbilical cord stricture and cord overcoiling may represent two distinct pathological entities commonly causing fetal demise. This observation reinforces the importance of a fetal autopsy with careful examination of the placenta and umbilical cord with documentation of the cord coil index.

Umbilical cord stricture and intrauterine fetal death

Umbilical cord stricture is an uncommon but distinctive condition associated with intrauterine fetal death. Although cases have been reported periodically since the last century, there has been considerable speculation as to whether the condition is real or a postmortem artifact. In the present study, 25 cases reported since 1925 are reviewed and 8 new cases are described. Clinically, a decrease in fetal movements is usually the only symptom during the second or third trimester of pregnancy and fetal death occurs soon after. The women's age, health, and previous history have shown no link with this condition, but a higher incidence is noted in twin pregnancies. Morphologically, most infants are macerated and an extremely narrow segment of umbilical cord is usually seen at the fetal end and rarely at the placental end or in multiple sites along the cord. Absence of Wharton's jelly, stenosis, or obliteration of cord vessels at the narrow segment and intravascular cord thrombosis are the major pathological features. The findings of this study support the view that the condition can cause fetal death and alerts both pathologists and clinicians to the important features identifying this cause of perinatal wastage.

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.