The influence of smoking during pregnancy on fetal growth. Considering daily cigarette consumption and the SGA rate according to length of gestation.
BACKGROUND
Smoking is the most important risk factor for adverse pregnancy outcomes in industrialized nations and is associated with, amongst other adverse effects, a higher rate of small-for-gestational-age (SGA) neonates. The rate of SGA neonates born before 32 weeks and its association with smoking have so far not been the focus of attention.


METHODS
Using data of 643,288 primiparous women from the German perinatal statistics of 1995-2000, we aimed to investigate this relationship. We also analyzed our data according to daily cigarette consumption.


RESULTS
We found that smoking during pregnancy was strongly associated with lower birth weight and higher SGA rates. This effect was especially pronounced in women >or=31 years. There was clear dose dependence with regard to daily cigarette consumption. An increase in SGA rates in smokers versus non-smokers can already be seen for very early preterm deliveries (31 weeks of gestation or less).


CONCLUSIONS
Our results allow the definition of groups of women who are at higher risk of SGA births. We show that especially older primiparous women (aged >or=31 years) who smoke >10 cigarettes a day are at increased risk of experiencing fetal growth restriction.
Voigt
M
M
Institute for Perinatal Auxology, Department of Paediatrics, University of Magdeburg, Germany. manfred.voigt@kliniksued-rostock.de
Briese
V
V
Jorch
G
G
Henrich
W
W
Schneider
K T M
KT
Straube
S
S
D015897:Comorbidity; D005260:Female; D005317:Fetal Growth Retardation / Q000453:epidemiology*; D005858:Germany / Q000453:epidemiology; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D018811:Maternal Exposure / Q000592:standards* / Q000706:statistics & numerical data*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology*; D018570:Risk Assessment; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology*