Effect of parity on first-trimester uterine artery Doppler indices and their predictive value for pregnancy complications.

Aim: To investigate the relationship between parity and first-trimester uterine artery Doppler indices and determine their predictive value for pregnancy complications.

Methods: In 679 singleton pregnancies (388 parous and 291 nulliparous) attending for routine care at 11-14 weeks of gestation, we recorded maternal characteristics, medical and obstetric history, the presence of protodiastolic notching and measured uterine artery resistance index (RI).

Results: Parous women had a lower prevalence of bilateral notches (64 vs.