Effects of smoking and fetal hypokinesia in early pregnancy

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.

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.

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).

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).