Progestagens can be used to control the estrus of bitches and cats for contraceptive purposes. This implies the occurrence of both reproductive and non-reproductive side effects. However, other contraceptive methods such as surgical sterilization are alternatives of equal value. To investigate this matter, a survey about the use of progestagens in small animal practices was sent to 120 Flemish veterinarians, 80 of whom responded. The results show that surgical sterilization is recommended by 98% of the veterinarians when owners require heat control of their animal. Nevertheless, the use of progestagens remains popular, with 71% of the practices using them with dogs and 58% using them with cats. The injectable formulations of medroxyprogesterone acetate and proligestone are mostly used in bitches, while the oral administration of megestrolacetate is most commonly used in cats. Increased appetite and body weight, neoplasia of the mammary gland and cystic endometrial hyperplasia/pyometra complex were the side effects most commonly noticed by veterinarians in both species.