title: The effects of preconception examinations on neural tube defects and the primary preventive measures: case-control study.
abstract: BACKGROUND
  Preventive measures for neural tube defects (NTDs) have been recommended for many years in China, but the compliance with these measures is unsatisfactory. This study aims to analyze the effects of preconception examinations on NTDs and its primary preventive measures.
  
  
  METHODS
  A 1:1 hospital-based case-control study was conducted. Four hundred and fifty-nine women who delivered or gestate infants/fetuses with NTDs from January 2006 to December 2008 were randomly selected and matched with women who delivered babies without obvious birth defects as controls in Shandong and Shanxi province. Multivariate conditional logistic regression was adopted.
  
  
  RESULTS
  Significant associations were shown between preconception examinations (OR = 0.461), health education (OR = 0.336), periconceptional folic acid supplement (OR = 0.295), periconceptional rational diet adjustment (OR = 0.278) and NTDs. In the case group, the rates of periconceptional folic acid supplement and health education conduction by women who had preconception examinations were significantly higher than that of those who had not, OR being 3.04 and 4.55, respectively (p < 0.05). Among the preventive effects on NTDs, preconception examinations and other NTDs primary preventive measures had significant combined effects and the combined effects with periconceptional folic acid supplement were the greatest, with OR of 0.04.
  
  
  CONCLUSIONS
  Preconception examinations have preventive effects on NTDs and can significantly improve the compliance of other NTDs primary preventive measures. In addition, preconception examinations and these measures have synergetic prevention effects, indicating the critical role played by preconception examinations on NTDs prevention.
authors.affiliation: a Department of Epidemiology and Health Statistics , School of Public Health, Shandong University , Jinan , China .|b Institute of Population Research, Peking University , Beijing , China .|c Rehabilitation Research Centre for Deaf Children , Beijing , China , and.
authors.forename: Rui
authors.initials: R
authors.lastname: Gong
authors.affiliation: a Department of Epidemiology and Health Statistics , School of Public Health, Shandong University , Jinan , China .
authors.forename: Zhi-Ping
authors.initials: ZP
authors.lastname: Wang
authors.affiliation: d Zhejiang Provincial Center for Disease Control and Prevention , Hangzhou City , Zhejiang Province , China.
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.affiliation: a Department of Epidemiology and Health Statistics , School of Public Health, Shandong University , Jinan , China .
authors.forename: Li-Jie
authors.initials: LJ
authors.lastname: Gao
authors.affiliation: a Department of Epidemiology and Health Statistics , School of Public Health, Shandong University , Jinan , China .
authors.forename: Qing-Bin
authors.initials: QB
authors.lastname: Lu
authors.affiliation: a Department of Epidemiology and Health Statistics , School of Public Health, Shandong University , Jinan , China .
authors.forename: Zhong-Tang
authors.initials: ZT
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage; D006397:Hematinics / Q000008:administration & dosage; D006801:Humans; D009436:Neural Tube Defects / Q000517:prevention & control*; D016742:Preconception Care; D011247:Pregnancy; D055815:Young Adult
chemical_list: D006397:Hematinics; D005492:Folic Acid
keywords: Preconception examinations; neural tube defects; primary prevention