Background: Smoking in pregnancy can cause a reduction in the transport of beta-carotene across the placenta, consequently reflecting on the concentrations of this micronutrient in the newborn baby.
Aims: This study determined the concentrations of beta-carotene in maternal blood and umbilical cord blood in a group of smokers and non-smokers.
Design and subjects: A total of 215 women and respective newborn babies were selected from a hospital in Joinville city, Brazil, between July and November 2002. Women were divided in two groups according to their smoking habits. beta-Carotene concentration was determined by high-performance liquid chromatography (HPLC). The difference between mean concentrations of beta-carotene in maternal blood and cord blood, in smokers and non-smokers, was determined by analysis of variance (ANOVA). The Student's t-test compared mean concentrations of beta-carotene in maternal blood and cord blood, and the mean ingestion of foods rich in beta-carotene by smokers and non-smokers.
Results: There was a statistical significant difference between the concentrations of beta-carotene in maternal blood (S=0.271 micromol/L, NS=0.450 micromol/L; P=0.001) and cord blood (S=0.028 micromol/L, NS=0.045 micromol/L; P=0.001) in smokers (S) and non-smokers (NS). The mean concentration of beta-carotene was significantly higher in maternal blood (0.398 micromol/L) than in cord blood (0.041 micromol/L) (P<0.001). The intake of foods rich in beta-carotene was lower in smokers, than in non-smokers (P=0.04).
Conclusions: The concentrations of beta-carotene in maternal blood and cord blood were influenced by the use of tobacco.