Recent Examples on the WebLisa Jacobson, an equine veterinarian in Colorado, says ovariectomy risks infection, internal bleeding and pain. Britta Lokting, Washington Post, 18 Nov. 2020 Their collaboration further showed a connection between hormones and cancer: mammary tumors decreased in female mice with ovariectomies while the tumors increased in pregnant mice. Leila Mcneill, Smithsonian, 20 Mar. 2018