The effects of smoking in pregnancy on factors influencing fetal growth.
OBJECTIVE
To evaluate the influence of maternal smoking during pregnancy on factors influencing fetal growth.


METHODS
Thirty newborns of smoking mothers were prospectively compared with 60 newborns of non-smoking mothers. Pre-albumin, albumin, triglycerides, glucose, insulin, insulin-like growth factor I, IGF binding protein 3, pH, lactic acid, erythropoietin and hemoglobin concentrations were measured in umbilical cord blood.


RESULTS
Infants of smoking mothers had a significantly lower birth weight (3418 +/- 533 vs. 3863 +/- 503 g; p < 0.001), length (50.5 +/- 2,6 vs. 52.3 +/- 1.9 cm; p < 0.001) and head circumference (34.6 +/- 1.8 vs. 35.8 +/- 1.1 cm; p < 0.001) than controls. They also had significantly lower insulin (3.2 (2.0-4.9) vs. 5.8 (4.6-7.1) mU/L; p = 0.008), insulin-like growth factor I (54.4 +/- 32.5 vs. 93.8 +/- 54.5 microg/L; p = 0.001) and IGF binding protein 3 (1664 +/- 432 vs. 1943 +/- 421 microg/L; p = 0.01) concentrations, than controls. Infants of smoking mothers also had significantly higher hemoglobin (167 +/- 14 vs. 157 +/- 13 g/L; p = 0.002) and erythropoietin (42.3 (25.1-72.4) vs. 26.3 (21.9-30.9) U/L; p = 0.03) than controls, but not pH or lactate concentrations. There was no significant difference in pre-albumin, albumin, triglycerides and glucose concentrations.


CONCLUSIONS
Smoking during pregnancy causes symmetrical fetal growth impairment, possibly due to decreased oxygen transport to the fetus and decreased concentrations of fetal insulin, insulin-like growth factor I and IGF binding protein 3.
Ingvarsson
Ragnar F
RF
University of Iceland, Faculty of Medicine, Landspitali University Hospital Iceland, Reykjavik, Iceland.
Bjarnason
Anton O
AO
Dagbjartsson
Atli
A
Hardardottir
Hildur
H
Haraldsson
Asgeir
A
Thorkelsson
Thordur
T
D000328:Adult; D001724:Birth Weight; D001827:Body Height; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D047109:Fetal Development; D006257:Head / Q000033:anatomy & histology; D006801:Humans; D007231:Infant, Newborn; D007328:Insulin / Q000032:analysis; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000032:analysis; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D011247:Pregnancy; D011446:Prospective Studies; D012907:Smoking / Q000009:adverse effects
D007328:Insulin; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I