title: [Reliability of self-reported maternal smoking during early lactation period].
abstract: Smoking cigarettes is very common among lactating women. The objective evaluation of an exposure to cigarette smoke is needed, as cotinine concentration. On many research a questionnaire is the only determinant of fact and intensification of smoking. The aim of this research was to establish a reliability of the questionnaire concerning cigarette smoking among lactating mothers by analyzing cotinine/creatinine ratio.
  
  
  METHODS
  In 51 lactating mothers (participants of the research on oxidative stress in Obstetrics Departments on 3rd day post partum) during check-up visit, on 30th day post partum a questionnaire concerning smoking cigarettes before, during pregnancy and after childbirth, and amount of cigarettes smoked was made. Samples of matutinal urine were deep freezed in - 700 till cotinine was evaluated immunoenzymatically. Women were divided into groups: I of non-smokers (32 women), II of smokers (19 women). Statistical analysis was made by means of unparametric test U Mann-Whitney.
  
  
  RESULTS
  Average cotinine/creatinine ratio was 33,8 ng/mg in group I; 1275.9 ng/mg in group II. Specificity and sensitivity of data earned by virtue of statement of correspondents was 81% and 89%. Test of cotinine concentration in urine demonstrated 100% sensitivity and 94% specificity compared to the cotinine/creatinine ratio. Directly proportional relationship was stated between amount of cigarette smoked and concentration of cotinine in urine (55.9 ng/ ml cotinine/cigarette).
  
  
  CONCLUSIONS
  A questionnaire should not be the only method evaluating smoking among lactating women. The concentration of cotinine shows slightly lower specificity than cotinine/creatinine ratio. Both tests can be dealt equivalent.
authors.affiliation: Klinika Pediatrii, Gastroenterologii, Hepatologii i Zywienia Dzieci Gdańskiego Uniwersytetu Medycznego. zyga2809@wp.pl
authors.forename: Maciej
authors.initials: M
authors.lastname: Zagierski
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Szlagatys-Sidorkiewicz
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Krzykowski
authors.forename: Michał
authors.initials: M
authors.lastname: Korzon
authors.forename: Anna
authors.initials: A
authors.lastname: Liberek
authors.forename: Grazyna
authors.initials: G
authors.lastname: Sikorska-Wiśniewska
authors.forename: Magdalena
authors.initials: M
authors.lastname: Góra-Gebka
authors.forename: Ewa
authors.initials: E
authors.lastname: Woś-Wasilewska
authors.forename: Barbara
authors.initials: B
authors.lastname: Kamińska
mesh_terms: D000328:Adult; D003367:Cotinine / Q000652:urine; D003404:Creatinine / Q000652:urine; D005260:Female; D006801:Humans; D007774:Lactation; D018811:Maternal Exposure / Q000706:statistics & numerical data*; D011044:Poland / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology* / Q000652:urine; D015203:Reproducibility of Results; D057566:Self Report / Q000592:standards*; D012680:Sensitivity and Specificity; D012907:Smoking / Q000453:epidemiology* / Q000652:urine; D011795:Surveys and Questionnaires; D014028:Tobacco Smoke Pollution / Q000706:statistics & numerical data*
chemical_list: D014028:Tobacco Smoke Pollution; D003404:Creatinine; D003367:Cotinine