Clinical manifestation of small-for-gestational-age risk pregnancy from smoking is gestational age dependent.
To determine the gestational age period at which small-for-gestational-age (SGA) risk from pregnancy smoking manifests, we conducted a retrospective cohort study of 266,782 live births in Kansas City, Missouri, from 1990 to 2004. Information was obtained from birth records. Newborns were stratified by gestation (< 32, 32 to 36, and > or = 37 weeks) and maternal pregnancy smoking. The outcome of interest was SGA. Covariates included factors associated with fetal growth restriction. SGA rates varied (8.4% versus 15.7% versus 9.9%), and relative risk from smoking increased (1.01 versus 1.46 versus 2.22) with gestational age periods. On multivariable logistic regression, smoking increased the odds ratio (OR) of SGA only among infants > or = 32 weeks; OR (95% confidence interval [CI], 1.26 [0.94, 1.68], 1.78 [1.59, 1.99], and 2.62 [2.52, 2.72]), for < 32, 32 to 36, and > or = 37 weeks, respectively. In conclusion, the clinical manifestation of SGA risk from smoking is gestational age dependent, only becoming apparent after 32 weeks of gestation.
Fitzgerald
Kerri
K
Children's Mercy Hospitals and Clinics, Kansas City, MO 64108, US.
Cai
Jinwen
J
Hoff
Gerald
G
Dew
Paul
P
Okah
Felix
F
D015331:Cohort Studies; D005260:Female; D047109:Fetal Development; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*