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Published on: December 2, 2017
Relationship between prepregnancy and early pregnancy uterine blood flow and resistance index
Sarah A Hale1, Adrienne Schonberg, Gary J Badger
1Department of Obstetrics, Gynecology and Reproductive Sciences, University of Vermont, Burlington, Vermont 05404, USA.
Abstract:
We evaluated the relationship between prepregnancy and early pregnancy uterine blood flow (UBF) and resistance index (RI). Nineteen nulliparous participants were studied during cycle day 8 + 4, and early pregnancy (13.4 + 1.6 weeks). Color Doppler ultrasound of both uterine arteries and maternal heart was performed to calculate uterine RI, volumetric UBF, and cardiac output (CO), respectively. We observed a strong negative association of uterine RI with prepregnancy UBF (r = -.82, P < .001) that weakened, but remained significant in early pregnancy (r =-.48, P = .04). Prepregnancy uterine index (UBF/CO) was significantly associated with early pregnancy uterine index; r = .48, P = .04). There was also a trend associating prepregnancy and early pregnancy volumetric UBF (r = .44, P = .068). Prepregnancy UBF may be a determinant of early pregnancy UBF and UBF may have independent value as a predictor of adverse pregnancy outcome.
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