Uterine activity and ductus venosus flow velocity patterns during the first stage of labor.
OBJECTIVE
To analyze the effects of uterine contractions on ductus venosus (DV) pulsatility during the first stage of labor.


METHODS
Twenty healthy women were examined. Measurements were taken at three stages of cervical dilatation (<4 cm, 4-7 cm and >or=8 cm) during and between contractions. Peak velocity during ventricular systole (S) and atrial contraction (A), pulsatility index for veins (DV PIV), ductus venosus index (DVI) and the S/A ratio were measured.


RESULTS
The DV was observed successfully in 16 cases. The mean S velocity did not change significantly (64 cm/s during and 65 cm/s between contractions). The mean A velocity decreased significantly from 35 cm/s measured between contractions to 29 cm/s during contractions (P<0.0001). The mean DV PIV and DVI were significantly higher during contractions (0.72 and 0.55) than between contractions (0.57 and 0.45) (P<0.0001). There were no significant differences in means between stages of cervical dilatation.


CONCLUSIONS
Significant differences during and between uterine contractions can be observed in DV pulsatility during normal labor.
Szunyogh
N
N
Department of Obstetrics and Gynecology, Comenius University, Jessenius Faculty of Medicine, Martin, Slovak Republic.
Zubor
P
P
Dokus
K
K
Galo
S
S
Visnovsky
J
J
Danko
J
J
D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology*; D005260:Female; D005333:Fetus / Q000098:blood supply*; D005865:Gestational Age; D006340:Heart Rate, Fetal / Q000502:physiology; D006801:Humans; D007747:Labor Stage, First / Q000502:physiology*; D008137:Longitudinal Studies; D011247:Pregnancy; D011673:Pulsatile Flow / Q000502:physiology*; D016216:Ultrasonography, Prenatal; D014590:Uterine Contraction / Q000502:physiology*; D014680:Veins / Q000502:physiology