NICOTINE AND CAFFEINE - INFLUENCE ON PRENATAL HEMODYNAMICS AND BEHAVIOR IN EARLY TWIN PREGNANCY

OBJECTIVE: To evaluate the effect of nicotine and caffeine in early mu ltiple pregnancies. STUDY DESIGN: Ten women with twin pregnancies volu nteered to take part in the study. Five mothers smoking >5 cigarettes/ d were investigated before and after smoking. Five women were investig ated before and after drinking coffee. Maternal hemodynamics, umbilica l bloodflow,fetal heart rate and twin behavior were longitudinally doc umented during a 30-minute session from 8 to 16 gestational weeks. Fet al behavior was analyzed from videotapes using a one-minute window. RE SULTS: The mean increase in maternal heart rate after smoking was 10 b pm (P < .005). After drinking coffee, it was 8 bpm (P < .01). The puls atility index of the umbilical artery showed a significant increase af ter smoking (P < .01). After coffee the increase was also significant (P < .05). Two of five behavioral parameters (swallowing and breathing ) demonstrated significant changes after the consumption of coffee (P < .001). CONCLUSION: This pilot study demonstrated significant effects of nicotine and caffeine consumption on maternal and fetal hemodynami cs. It seems worthwhile to study the influences of smoking and coffee consumption on early twin behavior in larger samples.