Prevalence of neural tube defects in the Province of Quebec, 1992

A retrospective study of neural tube defect (NTDs) was carried our among el ective terminations of pregnancies, stillbirths and live births to women re siding in two: regions of Quebec, in 1992. Primary data: sources included t he hospital administrative: data system MEDECHO, stillborn and infant death certificates, and the list of patients seen at three spina bifida clinics. Hospital records were reviewed. A total of 30 NTD cases were identified. T he prevalence: rate was 1.41 per 1,000, indicating a three-fold reduction i n frequency during the last, three decades. All 17 cranial defects but only ; 5 of 13 spinal defects were diagnosed during pregnancy. Elective terminat ions were performed at an average gestation of 18 weeks (range 11 to 21 wee ks). The MEDECHO file allows a complete identification of NTD cases, but di agnostic categories are not very specific and coding errors are present.