Open Access Open Badges Research article

Assessment of prenatal exposure to tobacco smoke by cotinine in cord blood for the evaluation of smoking control policies in Spain

Carme Puig1, Oriol Vall123, Óscar García-Algar11123*, Esther Papaseit4, Simona Pichini5, Esteve Saltó67 and Joan R Villalbí1089

Author Affiliations

1 Unitat de Recerca i Entorn (URIE), Institut Municipal d'Investigacions Mèdiques (IMIM)-Hospital del Mar, Parc de Salut Mar, Barcelona, Spain

2 Department of Pediatrics, Universitat Autònoma de Barcelona (UAB), Barcelona, Spain

3 Red Salud Materno Infantil y del Desarrollo (SAMID), RETIC Instituto Carlos III, Madrid, Spain

4 Unitat de Recerca en Farmacologia (URF), Institut Municipal d'Investigacions Mèdiques (IMIM)-Hospital del Mar, Parc de Salut Mar, Barcelona, Spain

5 Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Rome, Italy

6 Unitat de Recerca i Control del Tabaquisme, Institut Català d'Oncologia-IDIBELL, L'Hospitalet de Llobregat, Spain

7 Department of Public Health, Generalitat de Catalunya, Barcelona, Spain

8 Agència de Salut Pública de Barcelona, Barcelona, Spain

9 Institute of Biomedical Research (IIB Sant Pau), Barcelona, Spain

10 CIBER ESP, Barcelona, Spain

11 Hospital del Mar, Pg. Marítim 25-29, 08003 Barcelona, Spain

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BMC Pregnancy and Childbirth 2012, 12:26  doi:10.1186/1471-2393-12-26

Published: 5 April 2012



Over the last few years a decreasing trend in smoking has occurred not only in the general population but also during pregnancy. Several countries have implemented laws requiring all enclosed workplace and public places to be free of second hand smoke (SHS). In Spain, legislation to reduce SHS was implemented in 2005. The present study examines the possible effect of this legislation on prenatal SHS exposure.


Mothers and newborns were recruited from 3 independent studies performed in Hospital del Mar (Barcelona) and approved by the local Ethics Committee: 415 participated in a study in 1996-1998, 283 in 2002-2004 and 207 in 2008. A standard questionnaire, including neonatal and sociodemographic variables,tobacco use and exposure during pregnancy, was completed at delivery for all the participants in the three study groups. Fetal exposure to tobacco was studied by measuring cotinine in cord blood by radioimmunoassay (RIA).


32.8% of the pregnant women reported to smoke during pregnancy in 1996-1998, 25.9% in 2002-2004 and 34.1% in 2008. In the most recent group, the percentage of no prenatal SHS exposure (cord blood cotinine 0.2-1 ng/mL) showed an increase compared to the previous groups while the percentages of both: low (1.1-14 ng/mL) and very high (> 100 ng/mL) prenatal SHS exposure showed a decrease.


The results of the three study periods (1996-2008) demonstrated a significant increase in the percentage of newborns free from SHS exposure and a decrease in the percentage of newborns exposed to SHS during pregnancy, especially at the very high levels of exposure. A significant maternal smoking habit was noted in this geographical area with particular emphasis on immigrant pregnant smoking women.


Our study indicates that there is a significant maternal smoking habit in this geographical area. Our recommendation is that campaigns against smoking should be directed more specifically towards pregnant women with particular emphasis on non-native pregnant smokers due to the highest prevalence of tobacco consumption in the immigrant women.