Cabergoline versus calcium infusion in the prevention of ovarian hyperstimulation syndrome: a randomised controlled study

The aim of this study was to compare the efficacy of calcium infusion versus cabergoline in the prevention of ovarian hyperstimulation syndrome (OHSS) in IVF patients at high risk for OHSS. One hundred and seventy patients who were stimulated using the long luteal GnRH agonist protocol and at high risk for developing OHSS were randomised in a 1:1 ratio to cabergoline group and calcium gluconate group. In cabergoline group, 0.5 mg of cabergoline was administered once daily p.o. for eight days starting on the day of HCG administration. In calcium gluconate group, intravenous calcium gluconate (10%, 10 ml in 200 ml of physiologic saline) was administered daily for four days starting on the day of ovum pickup. Six patients in cabergoline group and eight patients in calcium gluconate group developed moderate OHSS. One patient in each group developed severe OHSS. The incidence of moderate/severe OHSS was comparable between both groups (8.24% vs. 10.59%, p value = .599, OR = 0.76, 95% CI [0.269-2.138]). The implantation, clinical and ongoing pregnancy rates were similar in the two groups (16.91% vs. 15.84%, p = .771, 35.29% vs. 32.94%, p = .746, and 30.59% vs. 28.24%, p = .736, respectively). In conclusion, calcium infusion and cabergoline have comparable effectiveness in the prevention of OHSS. Both drugs are well tolerated, cheap and have no adverse effects on the reproductive outcomes of IVF cycle.Clinical trial registration: The trial was registered on clinical trials.gov database [NCT02875587].Impact StatementWhat is already known on this subject? The effectiveness of cabergoline in the prevention of OHSS in IVF patients at high risk for OHSS is confirmed by overwhelming scientific evidence. Calcium infusion is a novel strategy for prevention of OHSS. Few studies reported the use of calcium infusion in the prevention of OHSS. A retrospective study and a randomised controlled study revealed that calcium infusion reduces the incidence of OHSS. Moreover, a quasi-randomised study revealed that calcium infusion is as effective as cabergoline in the prevention of OHSS.What the results of this study add? Calcium infusion and cabergoline have comparable effectiveness in the prevention of OHSS. Both drugs are well tolerated, cheap and have no adverse effects on the reproductive outcomes of IVF cycle.What the implications are of these findings for clinical practice and/or further research? Calcium infusion should be used to minimise the incidence of OHSS in IVF patients at high risk for OHSS.