GnRH Agonist Triggers in IUI Cycles

Clear Guideline Recommendation Against GnRH Agonist Use in IUI

The international fertility guidelines, as stated by the Human Reproduction Update, explicitly recommend against the use of GnRH agonists in IUI cycles with ovarian stimulation, due to the lack of increase in pregnancy rate despite increased multiple pregnancy rates and costs 1, 2, 3
The American Society for Reproductive Medicine and the European Society of Human Reproduction and Embryology recommend that tamoxifen, clomiphene citrate, or ≤75 IU gonadotropins per day can be used for ovarian stimulation in IUI cycles 1, 2
The guidelines advise against the application of GnRH agonists or antagonists in IUI cycles with ovarian stimulation, as stated by the Human Reproduction Update 1, 2

The appropriate triggering method for IUI cycles, as recommended by the Human Reproduction Update, is to detect spontaneous LH surge or trigger with hCG when 1-2 follicles are >15mm and <5 follicles are >10mm 1, 2, 4
The standard protocol for IUI involves performing single IUI 24-40 hours after hCG trigger or 1 day after detection of spontaneous LH surge, as stated by the Human Reproduction Update and the American College of Obstetricians and Gynecologists 1, 2, 4, 5
The standard hCG dose for IUI is 5,000 IU administered intramuscularly or subcutaneously, as recommended by the American Society for Reproductive Medicine 5

If concerned about OHSS risk in IUI cycles, the evidence-based prevention strategy, as recommended by the Human Reproduction Update and the European Society of Human Reproduction and Embryology, is to cancel the cycle, aspirate excess follicles, or convert to IVF when >2 follicles >15mm OR >5 follicles >10mm are present 1, 2, 3, 4, 6
The guidelines recommend using low-dose gonadotropins (≤75 IU/day) rather than higher doses to prevent OHSS, as stated by the American College of Obstetricians and Gynecologists and the Society for Assisted Reproductive Technology 3, 6
The use of clomiphene citrate or tamoxifen is considered as an alternative with lower multiple pregnancy rates, as recommended by the Human Reproduction Update and the American Society for Reproductive Medicine 3, 6
The multiple pregnancy risk increases dramatically with multifollicular development, with a risk of 6% with 2 dominant follicles, 14% with 3 follicles, and 10% with 4 follicles, highlighting the importance of primary prevention through cycle cancellation, as stated by the Human Reproduction Update 3