OBJECTIVETo 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).

METHODSSixty IVF-ET cycles from January 2008 to December 2011 were analyzed retrospectively. The clinical characteristics were compared between the various treatment cycles.

RESULTSCompared 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).

CONCLUSIONSFor 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.