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I have heard you can prevent OHSS with a Lupron trigger. Please tell me how this works and if you agree?


Ovarian Hyperstimulation Syndrome (OHSS) is a complication of ovarian stimulation with hormones as part of assisted reproduction treatment. OHSS is characterized by enlarged ovaries; “leaky vessels” with resultant fluid shifts – into the pelvis (ascites), tissue around the lungs (pleural effusion) and general body swelling (oedema); and a pro-thrombotic, inflammatory state. Typical symptoms of OHSS include abdominal pain, weight gain, nausea, vomiting and shortness of breath. OHSS can complicate between 3-6% of IVF cycles, with risk factors for developing OHSS including: polycystic ovary syndrome (PCOS), a high number of resting follicles (high “antral follicle count”), young age, low body weight, and previous history of OHSS. In the treatment cycle, a high number of mature egg follicles (>20-25 in each ovary) is a risk factor for developing OHSS. Circulating human chorionic gonadotrophin (hCG) is required to initiate OHSS. hCG is used in most standard IVF cycles to induce final egg (oocyte) maturation. hCG is also produced by the placenta, if pregnancy is achieved.

In certain treatment protocols, it is possible to use a GnRH-agonist (such as Lupron) to trigger final oocyte maturation. The GnRH-agonist induces the brain (pituitary gland) to release luteinizing hormone (LH), which also induces the final oocyte maturation. With the hCG trigger, hormone levels can be elevated for a prolonged time period. With the GnRH-agonist, hormone levels rapidly return to normal. The GnRH-agonist trigger (Lupron) will prevent OHSS from occurring; however it is associated with reduced pregnancy rates. Some fertility specialists would recommend that if GnRH-agonist trigger is used, the embryos obtained from the cycle should be frozen (cryo-preserved) and transferred back in a subsequent cycle, thereby avoiding the risk of OHSS & the reduced pregnancy rate of GnRH-agonist trigger. Another alternative is to provide add-back hormonal support.