Altered Fetal Cardiac Function in Smoking During Pregnancy

Maternal smoking during pregnancy remains a major public health issue and is associated with adverse perinatal outcomes. This study aimed to evaluate fetal cardiac functions in chronic maternal smoking during pregnancy and to compare them with non-smoker pregnant women. Forty-two smoker pregnant women between 24 and 34 weeks of gestation and gestational age-matched 44 non-smoker pregnant women were enrolled in this cross-sectional study. Fetal cardiac functions were measured using conventional Doppler echocardiography. The peak velocities of the mitral valve during early diastole (E) and atrial contraction (A) were measured, and the E/A ratio was calculated. The following time periods were also calculated; isovolumetric contraction time (ICT), isovolumetric relaxation time (IRT), and ejection time (ET). Then, the fetal left ventricle modified myocardial performance index (Mod-MPI) was calculated. No significant differences were noted between the groups in terms of E, A, and E/A ratio z-scores (p > 0.05). The ICT and IRT z-scores were found to be significantly higher in the study group compared with those in the control group (p = 0.001 and p = 0.034). Mod-MPI z-score was also found significantly higher in the study group than in the control group (p = 0.034). There was no significant difference between the groups in terms of ET (p > 0.05). The signs of systolic, diastolic, and global cardiac dysfunction were demonstrated in fetuses of pregnant women with chronic smoking. It, therefore, merits consideration that the fetal heart is also exposed to the detrimental effects of smoking.