Effects of Maternal Cigarette Smoking and Environmental Tobacco Smoke during Pregnancy on Birth Outcomes

• Main Authors: Hsien-Tsai Chiu, 邱顯財
• Other Authors: Hong-Dar Isaac Wu
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/22932803991866412769

碩士 === 中國醫藥大學 === 環境醫學研究所 === 93 === Background: This is a prospective study designed to investigate the adverse effects of maternal cigarette smoking and environmental tobacco smoke (ETS) during pregnancy on birth outcomes of neonates. Methods: Pregnant women seeking for prenatal care at two medical centers and two regional hospitals in Taichung were recruited as study subjects voluntarily. With subject consents, the cotinine levels in urine and serum were determined at three trimesters of gestation. Information was obtained on demographic characteristics, history of pregnancy, history of disease, volume of cigarette smoking, ETS exposure, and life style using a self-administrated questionnaire. Birth outcomes of the neonates were recorded by nurses at delivery. Results: The average urinary cotinine level at the second trimester were higher for smoking group (n = 46, 4.39 ± 5.65 ng/mL) than ETS group (n = 240, 3.00 ± 4.27 ng/mL) and non-smoking group (n = 235, 2.11 ± 3.13 ng/mL) (p=0.001). The average serum cotinine level at the second trimester also had the same trend among these groups. At all three trimesters, the urinary and serum cotinine levels elevated as the exposure to smoking and ETS increased. Results from generalized linear model with generalized estimating equation (GEE) approach showed that cotinine level increased as the gestation processed. In adjusted linear regression model, the neonates born to pregnant women of higher urinary cotinine level at the second trimester were 189 grams lighter in mean birth weight (p<0.001) and 1.12 centimeters shorter in mean body length (p<0.001), compared to the lowest quartile (urine cotinine of the second trimester were less than 0.284 ng/ml). Conclusions: Maternal smoking and ETS exposure in pregnant women may slow fetal growth. Cotinine level in serum or urine is a better predictor for birth weight and length than self-reported smoking status.