Can maternal-fetal hemodynamics influence prenatal development in dogs?

Area of Science:

• Veterinary Radiology
• Reproductive Ultrasound
• Fetal Medicine

Background:

• Early detection of embryonic and fetal abnormalities is crucial for reproductive outcomes.
• Standard ultrasound provides structural information, but early functional changes remain challenging to assess.
• Doppler velocimetry offers insights into vascular hemodynamics, potentially identifying abnormalities before structural changes are evident.

Purpose of the Study:

• To document embryonic and fetal ultrasound alterations in normal versus abnormal conceptuses.
• To compare uteroplacental and umbilical artery blood flow patterns between normal and abnormal conceptuses.
• To evaluate the efficacy of combined 2D and Doppler ultrasound in diagnosing conceptus abnormalities.

Main Methods:

• Sixty pregnancies were monitored weekly from mating/insemination.
• Two-dimensional ultrasound assessed conceptus morphology and extra-fetal structures.
• Doppler velocimetry measured resistivity index (RI) and pulsatility index (PI) in uteroplacental and umbilical arteries.

Main Results:

• 15.90% of fetuses exhibited embryonic abnormalities (resorption) and 5.68% showed fetal abnormalities.
• Abnormal conceptuses displayed reduced gestational vesicle diameter, abnormal contour, lack of viability, increased placental thickness, and altered fluid echogenicity.
• Elevated RI and PI in uteroplacental arteries were noted in embryonic resorption cases.
• Hemodynamic changes in uteroplacental and umbilical arteries preceded 2D alterations in abnormal fetuses.

Conclusions:

• Two-dimensional ultrasound is effective in identifying embryonic and fetal abnormalities.
• Combined Doppler ultrasound enables early detection of gestational and hemodynamic changes in abnormal conceptuses.
• This integrated approach can predict developmental influences in affected pregnancies.