The effect of parity on midgestational uterine artery Doppler findings in uncomplicated and low-risk pregnancies.
BACKGROUND
To establish the effect of parity on uteroplacental Doppler findings during midgestation in uncomplicated and low-risk pregnancies.


METHODS
Color flow pulse Doppler imaging of uterine arteries was performed on 760 uncomplicated singleton pregnancies fulfilling the study criteria at 19-24 weeks of gestation. Pulsatility indices (PIs) and bilateral notching were compared in nulliparous and parous pregnant women during various gestational weeks. The effects of maternal age, gestational age and parity on abnormal Doppler findings were assessed.


RESULTS
We found a significant difference in the prevalence of bilateral diastolic notch between nulliparous and parous women. From 19 to 24 weeks of gestation, a significant decrease in the PI values was observed (p < 0.001). The decrease in the PI values was significant in nulliparous, in contrast to parous women (p < 0.001). Parity had no effect on the mean PI, but parity was found to decrease the risk of bilateral notching (p < 0.05, R(2) = 0.031).


CONCLUSIONS
The mean indices are similar when the first and subsequent pregnancies are compared, especially after the 21st gestational week. Notching is more prominent in the first pregnancy. Parity has an effect on PIs in earlier weeks, and this effect is more pronounced in the appearance of bilateral notches.
Goynumer
G
G
Perinatology Department, Goztepe Education and Research Hospital, Istanbul, Turkey. goynumergo@ttmail.com
Yayla
M
M
Arisoy
R
R
Durukan
B
B
D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D003430:Cross-Sectional Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D008423:Maternal Age; D010298:Parity / Q000502:physiology*; D010920:Placenta / Q000098:blood supply*; D011247:Pregnancy / Q000502:physiology*; D012044:Regression Analysis; D018615:Ultrasonography, Doppler, Color / Q000379:methods; D055988:Uterine Artery / Q000000981:diagnostic imaging*