Doppler velocimetry of intraplacental fetal vessels in the second trimester: improving the prediction of pregnancy complications in high‐risk patients

Abstract

The purpose of our study was to assess the value of fetal intraplacental velocimetry in predicting adverse pregnancy outcome in high-risk patients. Thirty-two women with pregnancies of 22 to 25 weeks' gestation were evaluated. They had demonstrated abnormal first-trimester Doppler characteristics, yet had normal second-trimester umbilical artery velocimetry. Doppler waveforms were obtained and the ratio between intraplacental and umbilical artery resistance indices was calculated. Abnormally high ratios of intraplacental to umbilical artery resistance indices were associated with a significantly higher incidence of pregnancy complications. Among women with abnormal ratios, 17 (80%) of 21 pregnancies had later complications, whereas among those with normal ratios, only two (18%) of 11 women experienced later complications. This study demonstrates that analysis of the ratio between intraplacental and umbilical artery resistance indices in the second trimester improves the diagnostic value of Doppler velocimetry in pregnancies at risk for later obstetric complications.

Ultrasonographic signs of poor pregnancy outcome

“…It is for this reason that the PI and high RI in the 1st trimester should not be interpreted as a poor result, like it would be if made in the 2nd trimester as Jaffe explains [50]. This author explains [51] how the intervillous circulation persists until the late 1st trimester. In complicated pregnancies, analysed precociously, the uteroplacental circulation is different to that of normal pregnancies.…”

Spectral Doppler Index Mapping of the Umbilicoplacental Circulation and Pregnancy Outcome

“…The advantage of a detailed analysis of intraplacental Doppler waves is that it may identify fetoplacental circulation abnormalities earlier in gestation before these changes elicit an effect on the UA Doppler indices. Preliminary studies on the assessment of the intraplacental Doppler pulsatile indices (PI) during the second and third trimesters have been encouraging [15][16][17]. We have previously shown that the new Doppler method is reliable and can be used for the assessment of the fetoplacental circulation [1].The efficacy of this method in the prediction of adverse pregnancy outcome related to placental pathology has been described previously [17][18][19].…”

“…Current sensitive Doppler technology allows imaging of flow and direct measurements of Doppler indices in very small vessels [13][14][15]. The intraplacental fetal artery may be a more appropriate site for studying vascular resistance in the fetoplacental vascular tree [14][15][16]. However, meticulous analysis of the fetal intraplacental vessels using spectral Doppler sonography is tedious and time-consuming.…”

Role of 3-D Ultrasound in Clinical Obstetric Practice: Evolution Over 20 Years

“…There is evidence that the abnormalities revealed by umbilical Doppler represent pathologic vascular modifications in the villous tree of the placenta only in advanced stages of impaired placental function (Fok et al 1990;Trudinger et al 1987). Therefore, reduced intraplacental blood flow may precede increased umbilical resistance by several weeks, as far as the detection of this condition is concerned (Jaffe and Woods 1996;Yagel et al 1999). For these reasons, the development of new techniques for screening placental insufficiency at a much earlier stage are of great interest (Guimaraes Filho et al 2008).…”