Fertility after bilateral uterine artery embolization in a sheep model

Objective: To evaluate the impact of bilateral uterine artery embolization (UAE) upon fertility in sheep. Design: Prospective study. Setting: University-based interventional radiology, pathology, and reproductive physiology units. Animal(s): Nineteen control ewes, 10 ewes embolized with polyvinyl alcohol particles (PVA group), and 10 ewes embolized with Tris-acryl gelatin microspheres (TGMS group). Intervention(s): Bilateral UAE was performed with 600- to 1,000-mu m PVA particles or 700- to 900-mu m TGMS particles. Animals of three groups were synchronized and naturally inseminated. Main Outcome Measure(s): For each ewe, a hormonal follow-up was performed throughout the gestation. Gestation duration, number and weight of newborns, and fertility and gestation rates were recorded. Result(s): Mean number of estrus before insemination and gestation duration were not different between groups. There were 47 living newborns: 26 control, 9 PVA, and 12 TGMS. Overall birth weight of newborns was 3.7 +/- 0.9 kg for controls, 3.6 +/- 1.1 kg for TGMS, and 2.2 +/- 0.7 kg for PVA (which was statistically significant vs. control). In the PVA group, there was a statistically significant decrease of fertility rate and gestation rate vs. controls, but this was not the case in the TGMS group. Conclusion(s): Particles of PVA decrease fertility in sheep and lead to intrauterine growth retardation.