Background: Pituitary suppression by depot GnRH agonist may be excessive for ovarian stimulation in assisted reproduction technology. This study compares the efficacy of standard and half-dose depot triptorelin in a long protocol.
Methods: A total of 180 patients were randomized into two groups using sealed envelopes. Pituitary desensitization was obtained in group 1 (90 patients) with half-dose (1.87 mg) triptorelin depot in the mid-luteal phase of their menstrual cycle, and in group 2 (90 patients) with full-dose (3.75 mg) triptorelin.
Results: There was no premature LH surge, with LH levels being lower in the full-dose group (1.04+/-0.05 versus 0.7+/-0.06 IU/l on the day of hCG). The number of FSH ampoules used was lower in group 1 (42+/-2 versus 59+/-3). The numbers of mature oocytes (10.1+/-0.54 versus 7.4+/-0.55), of fertilized oocytes (8.24+/-0.35 versus 6.34+/-0.37) and of embryos (7.8+/-0.36 versus 5.9+/-0.37) were significantly higher in group 1. No significant differences were found in pregnancy (38.8 versus 25.3%), implantation (22.6 versus 13.8%) or abortion (6.1 versus 5.0%) rates. Cumulative pregnancy (fresh plus frozen embryo transfers: 56.8 versus 35.4%) rate was significantly higher in group 1.
Conclusion: A half-dose of depot triptorelin can be successfully used in ovarian stimulation for IVF and produce a higher number of good quality embryos with a good chance of implantation.