Maternal carriership of factor V Leiden associated with pathological uterine artery Doppler measurements during pregnancy

To determine whether increased vascular resistance in the uterine artery is associated with carriership of factor V Leiden, a retrospective study was undertaken of 231 pregnant women who were monitored with Doppler velocimetr y of the uterine arteries. These women had been part of a prospective study of 2480 pregnant women in whom factor V Leiden had been analysed. When com pared with non-carriers of factor V Leiden, carriers had a tendency towards an increased proportion of pathological Doppler measurements, including a significant increase in bilateral uterine artery notches (7/33 vs 16/198, r elative risk 3.1; 95% Cl 1.2-8.1). This suggests an increased vascular resi stance in the uteroplacental circulation among carriers of factor V Leiden.