BRD2 and ovarian hyperstimulation syndrome: In a meta-analysis performed by Bayram et al, in order to compare the safety, effectiveness in terms of ovulation, pregnancy, miscarriage, multiple pregnancy rate and ovarian hyper-stimulation syndrome (OHSS) in women with clomiphene-resistant polycystic ovary syndrome (PCOS) who had used recombinant FSH or urinary FSH, four randomized trials were identified.