title: Prevalence of smoking before and during pregnancy and changes in this habit during pregnancy in Northwest Russia: a Murmansk county birth registry study.
abstract: BACKGROUND
  Smoking during pregnancy leads to adverse maternal and birth outcomes. However, the prevalence of smoking among women in Russia has increased from < 5% in the 1980s to > 20% in the 2000s. We conducted a registry-based study in Murmansk County, Northwest Russia. Our aims were twofold: (i) assess the prevalence of smoking before and during pregnancy; and (ii) examine the socio-demographic factors associated with giving up smoking or reducing the number of cigarettes smoked once pregnancy was established.
  
  
  METHODS
  This study employs data from the population-based Murmansk County Birth Registry (MCBR) collected during 2006-2011. We used logistic regression to investigate associations between women's socio-demographic characteristics and changes in smoking habit during pregnancy. To avoid departure from uniform risk within specific delivery departments, we employed clustered robust standard errors.
  
  
  RESULTS
  Of all births registered in the MCBR, 25.2% of the mothers were smokers before pregnancy and 18.9% continued smoking during pregnancy. Cessation of smoking during pregnancy was associated with education, marital status and parity but not with maternal age, place of residence, and ethnicity. Women aged ≤ 20-24 years had higher odds of reducing the absolute numbers of cigarettes smoked per day during pregnancy than those aged ≥ 30-34 years. Moreover, smoking nulliparae and pregnant women who had one child were more likely to reduce the absolute numbers of cigarettes smoked per day compared to women having ≥ 2 children.
  
  
  CONCLUSIONS
  About 25.0% of smoking women in the Murmansk County in Northwest Russia quit smoking after awareness of the pregnancy, and one-third of them reduced the number cigarettes smoked during pregnancy. Our study demonstrates that women who have a higher education, husband, and are primiparous are more likely to quit smoking during pregnancy. Maternal age and number of children are indicators that influence reduction in smoking during pregnancy. Our findings are useful in identifying target groups for smoking intervention campaigns.
authors.affiliation: Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway. okh000@post.uit.no.|International School of Public Health, Northern State Medical University, office 1252, Troitsky avenue 51, Arkhangelsk, 163000, Russia. okh000@post.uit.no.
authors.forename: Olga A
authors.initials: OA
authors.lastname: Kharkova
authors.affiliation: Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway. alexandra.krettek@uit.no.|Department of Biomedicine and Public Health, School of Health and Education, University of Skövde, Skövde, Sweden. alexandra.krettek@uit.no.|Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden. alexandra.krettek@uit.no.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Krettek
authors.affiliation: International School of Public Health, Northern State Medical University, office 1252, Troitsky avenue 51, Arkhangelsk, 163000, Russia. andrei.grjibovski@fhi.no.|Department of International Public Health, Norwegian Institute of Public Health, Oslo, Norway. andrei.grjibovski@fhi.no.|Department of Preventive Medicine, International Kazakh-Turkish University, Turkestan, Kazakhstan. andrei.grjibovski@fhi.no.|North-Easten Federal University, Yakutsk, Russia. andrei.grjibovski@fhi.no.
authors.forename: Andrej M
authors.initials: AM
authors.lastname: Grjibovski
authors.affiliation: Department of Biochemistry and Biomedical Sciences, Hamilton, ON, Canada. nieboere@mcmaster.ca.
authors.forename: Evert
authors.initials: E
authors.lastname: Nieboer
authors.affiliation: Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway. jon.oyvind.odland@uit.no.|School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa. jon.oyvind.odland@uit.no.
authors.forename: Jon Øyvind
authors.initials: JØ
authors.lastname: Odland
mesh_terms: D000293:Adolescent; D000328:Adult; D016009:Chi-Square Distribution; D004522:Educational Status; D005260:Female; D006293:Health Promotion; D006801:Humans; D016015:Logistic Models; D017533:Marital Status; D008423:Maternal Age; D008425:Maternal Behavior; D010298:Parity; D010349:Patient Compliance; D011247:Pregnancy; D012042:Registries; D012426:Russia; D012907:Smoking / Q000009:adverse effects*; D016540:Smoking Cessation; D012959:Socioeconomic Factors; D055815:Young Adult