Objective: To evaluate the ovarian response and pregnancy outcomes in patients with excessive ovarian response receiving long-protocol pituitary down-regulation during repeated in vitro fertilization and embryo transfer (IVF-ET).
Methods: Sixty IVF-ET cycles from January 2008 to December 2011 were analyzed retrospectively. The clinical characteristics were compared between the various treatment cycles.
Results: Compared with those with the first treatment cycle, the patients receiving repeated cycles had a significantly older age (P<0.001), reduced initial doses of Gn (P=0.049), and moderately lowered estrogen level on the day of hCG administration (E₂) (P=0.027) and the number of oocytes retrieved (P=0.030). The high-quality embryo formation rate (P<0.001) and clinical pregnancy rate (P=0.009) were both significantly higher in patients with repeated cycles. The dose for down-regulation, total Gn dose, duration of Gn stimulation, number of two pronuclei (PN), number of fertilized oocyte, and the cancellation rate for a high risk of ovarian hyperstimulation syndrome (OHSS) were all comparable between the two groups (P>0.05). The recurrence rate of ovarian excessive respond was 40% (12/30).
Conclusions: For patients receiving repeated IVF treatment cycle with a high ovarian response, a smaller initial dose of Gn should be used to minimize the risk of hyper-response and improve the outcome of assisted reproductive treatment.