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Placental vascular biopsy through 3D power Doppler is a new and simple tool to routinely study placental vascularization in human pregnancy. Our results provide the validation of the technique demonstrating a good reproducibility of the 3D power Doppler parameters when applied to the study of the placental vascular tree in normal pregnancies.

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Our aim was to study placental circulation during the first trimester of normal pregnancy. For this purpose, 108 single pregnancies from 4 to 15 gestational weeks were evaluated through conventional Doppler ultrasonography. The flow velocity waveforms from the retrochorionic arteries (spiral-radial arteries) and the umbilical artery were assessed using the peak systolic velocity, resistive index, and pulsatility index). Intervillous flow velocity waveform was evaluated from the maximum velocity. The earliest color signal from the retrochorionic circulation was registered at 4.5 weeks along with gestational sac visualization. The venous Doppler signal from the intervillous space and the Doppler signal from the umbilical artery were recorded with an embryo visible from the end of week 5 onward. The retrochorionic, intervillous, and umbilical peak systolic velocities increase, whereas the resistive and pulsatility indices decrease progressively during early pregnancy with a significant correlation with gestational age. Similarly, intervillous maximum velocity gradually increases throughout the first trimester of pregnancy. Despite some methodologic problems related to Doppler technology and the vessels studied color Doppler sonography appears to be an adequate tool to assess the physiologic changes in the placental circulation during early pregnancy.

3D ultrasonography and PDA allow for an easier ovarian assessment in IVF cycles. The predictive value of IVF outcome suggests a high clinical usefulness of this new technique.

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We have evaluated 48 spontaneous ovarian cycles in 23 women by transabdominal Doppler ultrasound. A total of 1064 intraovarian flow velocity waveform recordings were obtained. The ultrasound assessment of follicular growth, and changes in the concentrations of urinary luteinizing hormone and serum progesterone were used to classify the cycles. After follicular rupture (and presumed ovulation) in 30 cycles, the intraovarian flow velocity waveform (dominant ovary) showed a turbulent flow during the luteal phase ('luteal conversion'). The maximal resistance index was lower compared to values obtained during the follicular phase, and from the contralateral ovary. The intraovarian flow velocity waveform from 12 abnormal cycles showed similar quantitative and qualitative changes. When ovulation did not occur (three cases of the luteinized unruptured follicle syndrome, three anovulatory cycles), there was no evidence of 'luteal conversion' and the velocimetry values were similar throughout the study. Intraovarian Doppler velocimetry makes it possible to distinguish between ovulatory and anovulatory cycles, and provides a non-invasive diagnosis of the luteinized unruptured follicle syndrome.

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