Effects of smoking and fetal hypokinesia in early pregnancy.

BACKGROUND: The aim of this study was to perform qualitative and quantitative ultrasound (US) monitoring of fetal movement in early pregnancy (gestational weeks 10-20) as a component of fetal behavior in women smokers.
METHODS: The study included three groups of 20 pregnant women each: non-smokers (group 1), smokers of an average of 10 cigarettes daily (group 2), and smokers of an average of >20 cigarettes daily (chronic smokers; group 3). Two-dimensional US study was performed once during gestational weeks 10-20 by the then standard method of fetal movement monitoring: 1) quantitative measurement of global fetal movements qualitatively verified as brisk or sluggish; 2) quantitative measurement of isolated spontaneous head movements; 3) quantitative measurement of isolated spontaneous arm movements; 4) quantitative measurement of isolated spontaneous leg movements; and 5) M-mode measurement of fetal heart rate.
RESULTS: The ratio of brisk to sluggish fetal movements was 82.8% to 17.2%, 79.01% to 20.98%, and 44.25% to 55.75% in groups 1, 2, and 3, respectively (p <0.001). The rate of isolated spontaneous head and arm movements and of the upper cerebral pattern (head and arm movements) was statistically significantly lower in group 3 as compared with groups 1 and 2 (p <0.001), whereas no statistical significance was recorded in isolated spontaneous leg movements (p >0.01). The rate of fetal tachycardia was also significant in group 3, whereas tachyarrhythmia was recorded in seven children born to group 3 mothers (p <0.001).
CONCLUSIONS: The present study of the effect of chronic tobacco hypoxia on the components of fetal behavior revealed a positive correlation between global and isolated fetal hypokinesia of the upper cerebral pattern (p <0.001), fetal tachycardia, and tachyarrhythmia in the group of mothers who were chronic smokers (p <0.001).