Evaluation of postpartum uterine involution in Kıvırcık ewes by pulsed-wave Doppler ultrasonography

The aim of this study was to determine the effects of oxytocin and carazolol administration on uterine blood flow by pulsed-wave Doppler ultrasonography (USG) and to evaluate the influences of these drugs on uterine involution. Thirty primiparous suckling Kiwircik ewes were divided into 3 groups: carazolol, oxytocin, and control. The ewes underwent transcutaneous B-mode USG in the 1st week after birth, and the examinations continued via transrectal USG until the 28th day of postpartum (pp). The pulsatility index (PI), resistance index (RI), and systolic/diastolic (S/D) velocity ratio were recorded for uterine artery by Doppler USG. At the end of the 21st day of pp, gravid uterine horn diameter reduction was best achieved in the carazolol-administered group. The PI values were found to be statistically significant (P˂0.001) on days 14, 21 pp. The mean RI values of uterine artery were statistically higher (P˂0.01) in the oxytocin-administered group. The highest RI value was detected on the 14th day of pp. The carazolol group had statistically (P˂0.05) higher mean S/D values when compared to other groups. In conclusion, the most effective drug used to accelerate involution was found to be carazolol. The drugs used in this study appeared to have a contraction effect on the uterine arteries. To the author’s knowledge, the effects of carazolol and oxytocin administration on uterine artery hemodynamics in ewes have not been reported in the literature. Therefore, it will be the first report in this field.