Stimulation regimens in Assisted Reproductive Technology (ART) programme: experience in the University Hospital,...

Ovarian stimulation is critical to the success of patients in Assisted Reproductive Technology (ART) programmes. We compared two stimulation regimes retrospectively for ART in the NUH programme. These were the 2:1 and the GnRHa-FSH/hMG regimes. The former was our first-line regime while the latter was used for cycles where there was a prior endogenous LH surge, previous poor response, or an elevated LH level between days three to five of the cycle. All cycles in our ART programme in 1991 were studied, except those for special research procedures, e.g. micro-insemination sperm transfer (MIST) cycles, a total of 241 cycles. Cancellation rates were 14.4% (21 of 146 cycles) and 37.3% (19 of 51 cycles) for the 2:1 and GnRHa-FSH/hMG regimes respectively (p > 0.001). For the 2:1 regime, the majority of cancellations were due to ovulation prior to the oocyte recovery (42.9%; nine of 21 cycles). However, for the GnRHa-FSH/hMG regime, almost all the cancellations were due to poor response (84.2%; 16 of 19 cycles). Fertilisation rates were lower for the 2:1 regime (for both IVF-ER and IVF-TET, where sperm quality was poorer) compared to the GnRHa-FSH/hMG (55.0 and 66.6% respectively; p < 0.001). Pregnancy rates were higher for the 2:1 regime when IVF-ER and IVF-TET were used (16.4% and 23.3% respectively per oocyte recovery, versus 9.8% and 18.8% respectively for the GnRHa-FSH/hMG regime).