Comparison of Resistance Index and Peak Systolic Velocity of Fetal Middle Cerebral Artery between Normal and Fetuses with Mutated Beta-Thalassemia Gene

Abstract

Background: Beta-thalassemia is the most common inherited single-gene disorder globally. In contrast to alpha-thalassemia, the role of resistance index (RI) and peak systolic velocity (PSV) of the middle cerebral artery (MCA) of the fetuses which are carriers for beta-thalassemia gene is not well understood. The objective of this study was to compare RI and PSV of the MCA in normal fetuses vs. fetuses with mutation of the beta-thalassemia gene. Methods: In this analytic study, 55 pregnant women with gestational age of 12 weeks and more were included consecutively. The pregnant women had history of giving birth to neonates with major betathalassemia or they or their husbands had minor beta-thalassemia. They underwent chorionic villus sampling (CVS). Twenty pregnant women without laboratory indices of beta-thalassemia were included as the control group. They underwent color Doppler ultrasound to measure RI and PSV of the fetal MCA. The data were analyzed using analysis of variance (ANOVA), Kruskal-Wallis test, chi-square test or the Fischer's exact test. Results: PSV of the MCA was significantly higher in fetuses with beta-thalassemia gene compared to control group (P< 0.05). No significant difference existed regarding RI of the MCA between minor, major beta-thalassemia and control groups (P> 0.05). Conclusion: PSV of the MCA of fetuses with major beta-thalassemia was higher than in normal fetuses.