ObjectiveTo assess whether, in GnRH agonist IVF cycles where there is a risk of ovarian hyperstimulation syndrome (OHSS), the addition of cabergoline to the hydroxyethyl starch (HES) infusion could decrease OHSS incidence and severity. Materials and methodsProspective randomized study. The population under study consisted of women undergoing IVF cycles with GnRH agonist protocols, at risk of OHSS (more than 20 follicles observed larger than 12mm in diameter and/or estradiol levels of 3000–5000pg/mL). Women received a slow infusion of 500mL of 6% HES during follicular aspiration alone or combined with 0.5mg cabergoline administration for 8 days, starting on the day of hCG administration. ResultsThe rates of OHSS (both early and late) were very similar in the HES alone group (3.19% (3/94)) and in the HES plus cabergoline group (5.68% (5/88)), as were the rates of severe cases of OHSS (1.06% and 2.27%). Pregnancy rates (PR) were also similar in the two groups (ongoing PR per transfer, 47.56% and 47.50%). CommentsThe co-administration of cabergoline in patients receiving HES due to OHSS risk did not reduce the rate or severity of OHSS in GnRH agonist IVF cycles.