Prevalence of encephalocele in Texas, 1999-2002.

Encephaloceles are congenital malformations characterized by a sac-like protrusion of the brain and/or its' covering membranes through an opening in the skull. The etiology of encephalocele is considered to be complex, and in most cases the causes of this condition remain elusive. The present study was undertaken to determine the prevalence of encephalocele among deliveries to Texas residents during 1999-2002, and to identify maternal and demographic factors associated with encephalocele. Data were examined from 125 infants and fetuses with encephalocele and no identified chromosome abnormality; identified in Texas and delivered in 1999-2002. During the same period there were 1,449,943 live births. The birth prevalence of encephalocele and both crude and adjusted prevalence ratios were estimated from these data. Compared with the offspring of White women, encephaloceles were significantly more common among the offspring of Hispanic women (adjusted prevalence ratio: 1.91, 95% confidence interval (CI) 1.34-2.70). In addition, compared to the offspring of women 25-29 years of age, encephaloceles were more common among the offspring of women 20-24 years of age (adjusted prevalence ratio: 1.52, 95% CI 1.01-2.27) and those less than 20 years of age (adjusted prevalence ratio: 1.55, 95% CI 0.98-2.45). These findings add to the existing literature on the descriptive epidemiology of encephalocele.