title: Risk factors for non-syndromic oral clefts: a matched case-control study in Hubei Province, China.
abstract: OBJECTIVE
  To explore the risk factors for CL/P in Hubei Province, China.
  
  
  METHODS
  A hospital-based, matched case-control study was conducted. One hundred and eight cases with CL/P were matched by age and sex with 108 normal controls. Their parents were retrospectively interviewed using a questionnaire. Univariate and multivariate analyses were used to calculate the relative risk by odds ratio and 95% confidence interval.
  
  
  RESULTS
  Univariate analysis identified ten factors as significantly related to CL/P (P < 0.05). Multivariate conditional logistic regression models showed that five of these factors were significantly associated with CL/P. Paternal occupational exposure (OR = 13.08, 95% CI: 2.35-72.86), first-trimester maternal illness (OR = 36.67, 95% CI: 5.37-250.36), first-trimester maternal bad mood (OR = 8.69, 95% CI: 1.35-55.84), first-trimester maternal diet of eggs or milk (≥5 meals per week, OR = 6.72, 95% CI: 1.23-36.69), and first-trimester maternal sexual activity (OR = 5.98, CI 95%:1.14-31.49) were risk factors for CL/P.
  
  
  CONCLUSIONS
  In our study, we identified that paternal occupational exposure, first-trimester maternal illness, first-trimester maternal bad mood, first-trimester maternal diet of eggs or milk (≥5 meals per week), and first-trimester maternal sexual activities were significantly associated with increased CL/P.
authors.affiliation: Department of Maternal and Children Health care, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: L
authors.initials: L
authors.lastname: Qi
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: M
authors.initials: M
authors.lastname: Yang
authors.forename: T
authors.initials: T
authors.lastname: Gong
authors.forename: M
authors.initials: M
authors.lastname: Shen
authors.forename: Y
authors.initials: Y
authors.lastname: Du
mesh_terms: D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D002971:Cleft Lip / Q000453:epidemiology / Q000209:etiology*; D002972:Cleft Palate / Q000453:epidemiology / Q000209:etiology*; D004032:Diet / Q000009:adverse effects; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology; D011297:Prenatal Exposure Delayed Effects / Q000209:etiology; D012307:Risk Factors; D011795:Surveys and Questionnaires
keywords: China; cleft lip with or without palate; matched case-control study; risk factors