prospective birth cohort study in Valencia, Spain
http://abc.go.com/watch/private-practice/127386/238346/right-here-right-now
Ferran Ballester , Marisa Estarlich , Carmen Iniguez , Sabrina Llop , Rosa
Ramon , Ana Esplugues , Marina Lacasana and Marisa Rebagliato
Environmental Health 2010, 9:6doi:10.1186/1476-069X-9-6
Published:29 January 2010
Abstract (provisional)
Background
Maternal exposure to air pollution has been related to fetal growth in a
number of recent scientific studies. The objective of this study was to
assess the association between exposure to air pollution during pregnancy
and anthropometric measures at birth in a cohort in Valencia, Spain.
Methods
Seven hundred and eighty-five pregnant women and their singleton newborns
participated in the study. Exposure to ambient nitrogen dioxide (NO2) was
estimated by means of land use regression. NO2 spatial estimations were
adjusted to correspond to relevant pregnancy periods (whole pregnancy and
trimesters) for each woman. Outcome variables were birth weight, length, and
head circumference (HC), along with being small for gestational age (SGA).
The association between exposure to residential outdoor NO2 and outcomes was
assessed controlling for potential confounders and examining the shape of
the relationship using generalized additive models (GAM).
Results
For continuous anthropometric measures, GAM indicated a change in slope at
NO2 concentrations of around 40 mcg/m3. NO2 exposure >40 mcg/m3 during the
first trimester was associated with a change in birth length of -0.27 cm
(95% CI: -0.51 to -0.03) and with a change in birth weight of -40.3 grams
(-96.3 to 15.6); the same exposure throughout the whole pregnancy was
associated with a change in birth HC of -0.17 cm (-0.34 to -0.003). The
shape of the relation was seen to be roughly linear for the risk of being
SGA. A 10 mcg/m3 increase in NO2 during the second trimester was associated
with being SGA-weight, OR: 1.37 (1.01-1.85). For SGA-length the estimate for
the same comparison was OR: 1.42 (0.89-2.25).
Conclusions
Prenatal exposure to traffic-related air pollution may reduce fetal growth.
Findings from this study provide further evidence of the need for developing
strategies to reduce air pollution in order to prevent risks to fetal health
and development.
