A longitudinal Doppler ultrasonographic assessment of the alterations in peripheral vascular resistance of uterine arteries and ultrasonographic findings of the involuting uterus during the puerperium.

OBJECTIVE: Our purpose was to assess the alterations in peripheral vascular resistance of uterine arteries in the puerperium. STUDY
DESIGN: In this longitudinal study 42 patients with uncomplicated pregnancies were examined with transabdominal color Doppler ultrasonography before and after delivery for 3 months. A total of 266 evaluations were performed.
RESULTS: Within 2 days after delivery the mean pulsatility index of uterine arteries had increased significantly from 0.73 +/- 0.15 to 1.19 +/- 0.36, and the prediastolic notch had reappeared. After 6 weeks the indexes had started to increase further and reached a level of 1.75 +/- 0.56 by the end of the third puerperal month.
CONCLUSIONS: Uterine vascular resistance increases soon after delivery. Puerperal changes in pulsatility indexes are triphasic. At the end of the fourteenth puerperal week pulsatility indexes are still much lower than those of nonpregnant women and all flow velocity waveforms represent a continuous end-diastolic component.