GnRH agonists have been used as a reversible contraceptive in wild and domestic cats with success. Although oocyte recovery was recorded, no data concerning pregnancy after induced reversibility was published. This study aimed to achieve pregnancy after induced estrous and ovulation in queens treated with deslorelin acetate. Five queens and one tom with proved fertility were used. All queens were treated with deslorelin (Suprelorin® 4.7 mg/animal). After 3 months of treatment, implants were removed and after 10 days queens received eCG (100 IU IM; Novormon) to induce estrous and 84 hours later hCG (100 IU IM; Vetecor) to induce ovulation. Twenty-four hours after ovulation induction queens were placed with tom, twice a day for two days (four copulations allowed/day). Thirty days after ovulation induction females were submitted to ultrasound to confirm pregnancy. No formal analysis was done. After contraceptive treatment all queens entered anestrous, after a brief ovarian stimulation due to treatment. After implants were removed, queens responded positively to estrous/ovulation induction and allowed copulation. However, none of the queens were pregnant at ultrasound examination. Estrous and ovulation protocol used have been described before with success, including queens treated with deslorelin; however, in that study no attempt of pregnancy was performed. We concluded that the first induced estrous and ovulation after a short-term contraceptive treatment with deslorelin should not be used for attempted pregnancies, hormonal analysis and immunohistochemistry will be performed to investigate progesterone production (premature luteolysis in bitches treated with GnRH agonists was reported previously) and uterus preparation to embryo implantation.

Financial support: FAPESP 2011/23318-0.