title: [Case control study on risk factors of congenital microtia].
abstract: OBJECTIVE
  To identify the risk factors associated with congenital microtia.
  
  
  METHODS
  A case-control, retrospective study was performed. A total of 207 cases of congenital microtia and 209 age-frequently-matched controls were interviewed individually according to the uniform questionnaire. The questionnaire included: (1) Essential information about patients and their parents. (2) First trimester diseases and medication of mother. (3) Past gestation history of mother. (4) Family history and life style of the parent. The available data were analyzed by chi-square test and multivariate Logistic regression model.
  
  
  RESULTS
  The factors, such as gender (OR = 5.893), first trimester disease of mother (OR = 34.49) and medication (OR = 4.299), excessive drinking and smoking of father (OR = 4. 347, OR = 4.304), non-primiparous parity (OR = 9.524), abortion (spontaneous and induced, OR = 1.723), low-education of mother (OR = 2.275) were risk factors contributing to microtia in multivariate study. The factors, such as tea (OR = 0.179) were protective factors in multivariate study.
  
  
  CONCLUSIONS
  Multi-risks factors are contributing to microtia. Preventive measures according to risk factors should be put forward.
authors: Plastic Surgery Hospital, Chinese Academy of Medical Science, Beijing, China. dujiamei@yahoo.com.cn
authors: Jia-mei
authors: JM
authors: Du
authors: Wan-hou
authors: WH
authors: Guo
authors: Juan
authors: J
authors: Han
authors: Hong-xing
authors: HX
authors: Zhuang