Progestagens can be used to control the estrus of bitches and cats for contraceptive purposes. This implies theoccurrence of both reproductive and non-reproductive side effects. However, other contraceptive methods such assurgical sterilization are alternatives of equal value. To investigate this matter, a survey about the use of progestagensin small animal practices was sent to 120 Flemish veterinarians, 80 of whom responded. The results show that surgicalsterilization 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% usingthem with cats. The injectable formulations of medroxyprogesterone acetate and proligestone are mostly used inbitches, while the oral administration of megestrolacetate is most commonly used in cats. Increased appetite and bodyweight, neoplasia of the mammary gland and cystic endometrial hyperplasia/pyometra complex were the side effectsmost commonly noticed by veterinarians in both species.