About 1 to 2 percent of women undergoing ovarian stimulation develop a severe form of ovarian hyperstimulation syndrome. Severe OHSS can be life-threatening. Complications may include. Fluid collection in the abdomen and sometimes the chest. Electrolyte disturbances. Blood clots in large vessels, usually in the legs. Kidney failure. Twisting of an ovary. Rupture of a cyst in an ovary, which can lead to serious bleeding. Breathing problems. Pregnancy loss from miscarriage or termination because of complications. To decrease your chances of developing ovarian hyper stimulation syndrome, you’ll need an individualized plan for your fertility medications. Expect your doctor to carefully monitor each treatment cycle, including frequent ultrasounds to check the development of follicles and blood tests to check your hormone levels.