In vitro fertilisation with recombinant follicle stimulating hormone requires less IU usage compared with highly purified human menopausal gonadotrophin: results from a European retrospective observational chart review

BACKGROUND: Previous studies have reported conflicting results for the comparative doses of recombinant follicle stimulating hormone (rFSH) and highly purified human menopausal gonadotrophin (hMG-HP) required per cycle of in vitro fertilisation (IVF); the aim of this study was to determine the average total usage of rFSH versus hMG-HP in a 'real-world' setting using routine clinical practice. METHODS: This retrospective chart review of databases from four European countries investigated gonadotrophin usage, oocyte and embryo yield, and pregnancy outcomes in IVF cycles (± intra-cytoplasmic sperm injection) using rFSH or hMG-HP alone. Included patients met the National Institute for Health and Clinical Excellence (NICE) guideline criteria for IVF and received either rFSH or hMG-HP. Statistical tests were conducted at 5% significance using Chi-square or t-tests. RESULTS: Of 30,630 IVF cycles included in this review, 74% used rFSH and 26% used hMG-HP. A significantly lower drug usage per cycle for rFSH than hMG-HP (2072.53 +/- 76.73 IU vs. 2540.14 +/- 883.08 IU, 22.6% higher for hMG-HP; p < 0.01) was demonstrated. The median starting dose was also significantly lower for rFSH than for hMG-HP (150 IU vs. 225 IU, 50% higher for hMG-HP, p < 0.01). The average oocyte yield per IVF cycle in patients treated with rFSH was significantly greater than with hMG-HP (10.80 +/- 6.02 vs. 9.77 +/- 5.53; p < 0.01), as was the average mature oocyte yield (8.58 +/- 5.27 vs. 7.72 +/- 4.59; p < 0.01). No significant differences were observed in pregnancy outcomes including spontaneous abortion between the two treatments. There was a significantly higher rate of OHSS (all grades) with rFSH (18.92% vs. 14.09%; p < 0.0001). The hospitalisation rate due to OHSS was low but significantly higher in the rFSH group (1.07% of cycles started vs. 0.67% of cycles started with rFSH and hMG-HP, respectively; p = 0.002). CONCLUSIONS: Based on these results, IVF treatment cycles with rFSH yield statistically more oocytes (and more mature oocytes), using significantly less IU per cycle, versus hMG-HP. The incidence of all OHSS and hospitalisations due to OHSS was significantly higher in the rFSH cycles compared to the hMG-HP cycles. However, the absolute incidence of hospitalisations due to OHSS was similar to that reported previously. These results suggest that the perceived required dosage with rFSH is currently over-estimated, and the higher unit cost of rFSH may be offset by a lower required dosage compared with hMG-HP.