Prevention of Ovarian Hyperstimulation Syndrome

Ovarian hyperstimulation syndrome (OHSS) is the most serious iatrogenic complication of excessive response to ovulation induction or ovarian stimulation during in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment cycles [1–5] The incidence of OHSS has been estimated at 20–33% for mild cases, 3–6% for moderate cases, and 0.1% and 2% for severe cases [6–8]. OHSS is characterized by bilateral, multiple follicular and theca-lutein ovarian cysts (Figure 15.1) and an acute shift in body fluid distribution resulting in ascites (Figure 15.2) and pleural effusion. Rizk and Smitz [9], in an analytical study of the factors that influence the incidence of OHSS, found a wide variation among different centers.