The recurrence risk for neural tube defects in the United States: A collaborative study

Abstract

To determine the recurrence risk for patients with one prior pregnancy affected with neural tube defects (NTD), the authors have pooled data from eight testing centers. In 831 pregnancies studied because one sib was affected with an NTD, the recurrence rate was 3.0%, with 95% confidence limits of 2.0-4.3%, and 99% confidence limits of 1.8-4.8%. The recurrent lesion, whether spina bifida or anencephaly, tended to be concordant with the first to a significant degree. Only 12.2% of recurrent NTD were different from the first, with 95% confidence limits of 4.1-26.2%, and 99% confidence limits of 1.7-30.9%. Both an accurate recurrence risk and the information that a recurrent NTD lesions tends to be concordant with that in the first affected child are useful in the genetic counseling of patients in the United States and in the selection of appropriate prenatal diagnostic studies.

Congenital anomalies of the vertebral column: a case study on ancient and modern Egypt

“…Also, the prevalence in populations may vary at different times for unknown reasons (Cowakock et al, 1980;Hussein, 1988). 1/1000 was the prevalence of the spina bifida in the US (Holmes et al, 1976;Greenberg et al, 1983), and a figure of 1.08/1000 in Canada (Hunter, 1984) is significantly higher than the rate of 0.84/1000 observed in Columbia (Trinuble & Baird, 1978).…”

Use of genetic counselling services for neural tube defects

“…Although there may be some concordance for the type of NTD among sibs [Carter and Evans, 1973;Cowchock et al, 1980;Toriello and Higgins, 19851, this finding is not universal and does not appear to be the case in B.C. [McBride, 19791.…”

“…These figures are considerably higher than the incidence of NTDs in the general population of B.C., which is 1.6/1,000 births or 0.16% [Trimble and Baird, 19781. Although it has been reported that there may be concordance for the type of NTD present in sibs [Carter and Evans, 1973;Cowchock et al, 1980;Toriello and Higgins, 19851, this has not always been observed and does not appear to be the case in B.C. [McBride, 19791. Open spina bifida and anencephaly can be diagnosed prenatally by ultrasonography [Brock, 19831 and amniocentesis [Brock and Stucliffe, 19721.…”

Public health projects for preventing the recurrence of neural tube defects in the United States

“…Among mothers who have had a previous NTD-affected pregnancy, the risk of a subsequent pregnancy affected by an NTD is approximately 3% (Cowchock et al, 1980;Grosse and Collins, 2007), which is more than fortyfold higher than the background occurrence.…”