ABSTRACT
In this chapter, risk factors for ovarian hyperstimulation syndrome (OHSS) are restricted to so-called controlled ovarian hyperstimulation (COH). The primary risks for OHSS in ovulation induction (01) are not dealt with, since the aim of 01 (preferably obtaining one follicle) is differ ent from that of COH (obtaining multiple folli cles), and a low number of follicles excludes OHSS.