[Early diastolic incisures in uteroplacental blood vessels. Experiences in patients with uneventful pregnancy and labor].

The frequency of diastolic notching in uteroplacental arteries was examined in a collective of 510 patients with uneventful pregnancies and deliveries. Notching appeared to be more frequent in the uterine than arcuate artery. It was seen to increase as pregnancy progressed and was markedly higher in the third compared with the second trimester. Uteroplacental notching occurred more frequently unilaterally and mainly affected contralateral sites of the placenta. Bilateral and retroplacental notching was the exception in normal pregnancies.