title: [Upper and lower neural tube defects: prevalence and association with illnesses and drugs].
abstract: OBJECTIVE
  To determine the prevalence of upper and lower neural tube defects and identify its association with the exposure to illnesses and drugs during pregnancy.
  
  
  METHODS
  This is a case-control study of 107 newborns with upper neural tube defects, 59 with lower neural tube defects, and 166 newborns without malformations, in 56,926 consecutive births between 1989 and 1997. The exposure was documented by a direct interview to the mother of those subject of study. The association was measured by the odds ratios, with confidence interval of 95%.
  
  
  RESULTS
  The prevalence of upper neural tube defects was of 1.9 for 1,000 newborn (alive or dead) and of lower neural tube defects of 1.0 for 1,000. The exposure to illnesses of less than a month of duration was associated with upper neural tube defects (OR = 3.11; IC = 1.34-7.39) the most important was flu; also the exposure to drugs (OR = 5.85; IC = 2.97-11.62), the most prominent was acetaminophen. These factors of risk were not associated with lower neural tube defects. The mother's occupation, illness of more than a month of duration and X-ray exposure were not associated with of upper and lower neural tube defects.
  
  
  CONCLUSIONS
  More studies are needed in the association among illnesses of less than a month of duration and drugs with upper neural tube defects. The different exposure frequencies between upper and lower neural tube defects suggest heterogeneity.
authors.affiliation: División de Pediatría, Hospital Civil de Guadalajara Dr. Juan I. Menchaca, Departamento de Clínicas de la Reproducción Humana y Crecimiento infantil, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco.
authors.forename: J Jesús
authors.initials: JJ
authors.lastname: Pérez-Molina
authors.forename: Noé
authors.initials: N
authors.lastname: Alfaro-Alfaro
authors.forename: Cristina
authors.initials: C
authors.lastname: Ochoa-Ponce
mesh_terms: D000082:Acetaminophen / Q000009:adverse effects; D018712:Analgesics, Non-Narcotic / Q000009:adverse effects; D000757:Anencephaly / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology; D016022:Case-Control Studies; D016001:Confidence Intervals; D003241:Consanguinity; D003430:Cross-Sectional Studies; D004677:Encephalocele / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology; D005260:Female; D005313:Fetal Death / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008588:Meningocele / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology; D008591:Meningomyelocele / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology; D009436:Neural Tube Defects / Q000139:chemically induced / Q000453:epidemiology* / Q000209:etiology; D016017:Odds Ratio; D011247:Pregnancy; D011248:Pregnancy Complications; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors
chemical_list: D018712:Analgesics, Non-Narcotic; D000082:Acetaminophen