Objective: To investigate the effect of the vaginal application of the prostaglandin (PGE1) analogue gemeprost on the vascular resistance of the main uterine arteries in early pregnancy.
Design: A prospective observational study.
Subjects: Twenty-one patients seeking legal termination of pregnancy at 7-12 weeks gestation.
Methods: Pulsatility indices for the main uterine arteries were measured by vaginal colour Doppler ultrasound before and 3 to 4 h after vaginal application of the PGE1 analogue gemeprost.
Results: A significant increase of pulsatility indices was observed (P < 0.001) which was not affected by parity or gestational age. The change was similar in both uterine arteries, and placental lateralisation did not affect the results. All fetuses were still alive at the second examination.
Conclusions: Vaginal application of prostaglandin analogue gemeprost in early pregnancy increases the vascular resistance of uterine arteries. This may be caused by a direct vasoconstrictory effect or be secondary to uterine contractions.