Diseases and Conditions

Ovarian hyperstimulation syndrome

Risk factors

Sometimes, OHSS happens in women with no risk factors at all. But factors that are known to increase your risk of OHSS include:

  • Polycystic ovary syndrome — a common reproductive disorder that causes irregular menstrual periods, excess hair growth and unusual appearance of the ovaries on ultrasound examination
  • Large number of follicles
  • Age under 35
  • Low body weight
  • High or steeply increasing level of estradiol (estrogen) before an HCG trigger shot
  • Previous episodes of OHSS