Objective To assess endothelial function in normal pregnancy by non-invasiv
e methods.
Methods Flow-mediated dilatation of the brachial artery was measured by ult
rasonography 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 d
ilatation (8.84 +/- 3.18%) was significantly higher than the nonpregnant co
ntrols (P = 0.002), but after 30 weeks of gestation there was a decrease to
prepregnancy levels. Resting vessel diameter and blood flow were significa
ntly increased in pregnancy, mainly after 30 weeks' gestation (P < 0.001, P
< 0.001, respectively). Flow-mediated dilatation was significantly correla
ted to resting vessel diameter and reactive hyperemia.
Conclusion Normal pregnancy is associated with enhanced endothelial functio
n which is apparent from at least 10 weeks' gestation.