First trimester uterine artery pulsatility index in a normal pregnancy

Abstract

Objectives: To determine the range of distribution of first trimester uterine artery pulsatility index (Ut-A PI) in pregnancies uncomplicated with pre-eclampsia (PE) and fetal growth restriction (FGR) and to determine if there is a difference between 12+0-12+6 and 13+0-13+6 distribution. Methods: Along with first trimester aneuploidy- screening, all women underwent Ut-A PI measurement done by FMF protocol (transabdominal approach, mid-sagittal cervical view, level of internal cervical os, PSV > 60 cm/s, angle of insonation < 30◦ ). Mean PI from both uterine arteries was calculated. Women were monitoring throughout the pregnancy. Data from pregnancies uncomplicated with PE and/or FRG were evaluated. Results: Total of 94 women represented data pool: 47 of them were evaluated at 12+0-12+6 week of gestation and the rest 47 at 13+0-13+6 week of gestation. During 12+0-12+6 week of gestation Ut-a PI ranged from 1.0 to 2.8 with mean of 1.8, median of 1.75 and IQR 0.615. Ut-a PI during 13+0-13+6 week of gestation ranged from 0.71-2.74 with mean of 1.57, median of 1.6 and IQR 0.68. The difference in Ut- A PI between these two intervals had p value of 0.007. Conclusions: In a normal i.e. a pregnancy uncomplicated with PE and/or FGR uterine artery pulsatility index is lower in 13+ in comparison with 12+ week of pregnancy (median of 1.6 versus the median of 1.75) which represents a statically significant difference (p < 0.01).