Assessment of endothelial function in normal twin pregnancy

Abstract

Objective: To assess the maternal endothelial function in normal twin pregnancy. Design: Cross-sectional study. Subjects: Endothelial function was investigated in 74 women with normal twin pregnancy at 11-3 0 weeks of gestation and the results were compared to previous reported findings in 98 women with normal singleton pregnancy and 19 nonpregnant controls. Methods: Endothelial function was assessed by measuring the changes of the brachial artery diameter in response to reactive hyperemia (flow-mediated dilatation) using external high resolution ultrasound. Results: Flow-mediated dilatation of the brachial artery in both twin and singleton pregnancies was significantly higher than in non-pregnant women (P = 0.002 and P = 0.02, respectively). However, there was no significant difference in flow-mediated dilatation between women with twin and singleton pregnancy (9.61 ± 4.36 vs. 8.84 ± 3.18, P = 0.38). Resting vessel size, baseline flow and reactive hyperemia did not change significantly with gestation in twin pregnancy and were similar to values in singleton pregnancies and controls. Conclusion: Our findings indicate that although in pregnancy endothelial function is enhanced, this change may not be affected by the number of fetoplacental units present.