Variation in the uterine arteries Doppler parameters when obtained transvaginally or transabdominally at different sampling locations.

INTRODUCTION

To evaluate differences in Doppler velocimetry parameters when the uterine arteries (UtA) are evaluated transabdominally (TA) at different sampling locations and transvaginally (TV).

MATERIALS AND

METHODS

Five hundred and fifty-seven pregnant women were evaluated between 11 and 39 weeks of gestation. The mean UtA pulsatility index (PI) and prevalence of bilateral notching were obtained at four different locations: (1) TA just above the crossing with the iliac artery; (2) TA just below the crossing with the iliac artery; (3) TA well above approximately 3 cm away from the crossing with the iliac artery; and (4) TV at the point closest to the internal cervical os. Measurements obtained just above the external iliac artery were considered the standard for comparison. Differences among different locations per gestational week were calculated.

RESULTS

The mean UtA-PI and prevalence of bilateral notching were similar when the uterine arteries were sampled TA just above or just below the crossing with the external iliac artery. The mean UtA-PI values and prevalence of bilateral notching were significantly higher (p < .0001) when obtained TV and significantly lower when obtained 3 cm above the crossing with the external iliac artery (p = .004), as compared to the standard plane just above the crossing.

CONCLUSION

The mean UtA-PI and prevalence of bilateral notching vary significantly when the uterine arteries are sampled far above the crossing with the external iliac artery or when obtained transvaginally.Key MessageThe predictive performance of the uterine arteries during pregnancy can significantly vary in relation to the approach selected for evaluation and to the location of the Doppler sampling gate.