Purpose: Mild controlled ovarian hyperstimulation (COH), combined with oocyte retrieval (OR) under local anaesthesia (LA), may provide low-impact IVF. Since a single injection of corifollitrophin alfa (CFA) provides 7 days of COH, we hypothesised that clomiphene-citrate (CC) followed by CFA may provide adequate COH response from one single FSH injection. Therefore, the aim was to assess IVF outcomes after a novel clomiphene citrate/CFA (CC/CFA) protocol, compared to women undergoing standard rFSH COH protocols (good prognosis comparative cohort:GPCC) in a 1:2 matched design. Materials and methods: In this pilot study of 25 patients (ANZCTR id:ACTRN12612000740897, MINIVA:Minimal_Stimulation_in_IVF), we examined the effectiveness of oral clomiphene (100 mg-days 2–6) followed by CFA in a GnRH antagonist protocol producing a single injection COH stimulation regime. All OR were conducted under LA pre-ovarian block. Cycle outcomes were compared to a matched good prognosis comparative cohort (GPCC) undergoing standard rFSH COH. Results: Mild stimulation was achieved with less oocytes being collected compared to the GPCC (6.4 ± 0.7 vs. 10.7 ± 0.9, p < 0.001), resulting in a reduced number of good quality embryos available for transfer/cryopreservation (3.7 ± 0.6 vs. 5.7 ± 0.5, p = 0.01). While embryo quality was similar between the two groups, endometrial thickness was significantly lower in the group receiving CC/CFA. Pregnancy rates were significantly lower in the CC/CFA cohort compared to GPCC (31.8 vs. 57.1%, p = 0.04) and 44% of CC/CFA participants required supplemental rFSH in order to achieve the hCG trigger criteria. Conclusion: Sequential clomiphene CFA protocol does not appear to be an optimal regime for low impact IVF treatment as it does not provide adequate COH from a single CFA injection and results in lower fresh embryo transfer pregnancy rates and fewer embryos for cryopreservation.
- Controlled ovarian hyperstimulation
- Corifollitrophin alfa