Non-invasive assessment of endothelial function in normal pregnancy

Objective To assess endothelial function in normal pregnancy by non-invasive methods. Methods Flow-mediated dilatation of the brachial artery was measured by ultrasonography in 157 women with normal singleton pregnancies between 10 and 40 weeks' gestation and 19 non-pregnant controls. Results Flow-mediated dilatation in the non-pregnant controls was 6.42 +/- 2.45%. In pregnant women, between 10 and 30 weeks, the mean flow-mediated dilatation (8.84 +/- 3.18%) was significantly higher than the nonpregnant controls (P = 0.002), but after 30 weeks of gestation there was a decrease to prepregnancy levels. Resting vessel diameter and blood flow were significantly increased in pregnancy, mainly after 30 weeks' gestation (P < 0.001, P < 0.001, respectively). Flow-mediated dilatation was significantly correlated to resting vessel diameter and reactive hyperemia. Conclusion Normal pregnancy is associated with enhanced endothelial function which is apparent from at least 10 weeks' gestation.