A large Northern European observational study of follitropin alpha filled-by-mass pre-filled pen

This prospective observational post-marketing survey aimed at studying the efficacy and convenience of the follitropin alpha filled-by-mass (FbM) pre-filled pen for patients in routine use. These data were analysed among 3196 non-selected treatment cycles and couples in seven Northern European countries. Valuable information was also obtained regarding the routine assisted reproduction treatment protocols used in Northern Europe. Out of 3196 cycles, human chorionic gonadotrophin (HCG) was administered in 3104 (97.2%), and an embryo transfer was carried out in 2766 cycles (86.5%). A positive HCG was recorded in 997 cycles (31.2% per started cycle and 36.0% per embryo transfer). The overall clinical pregnancy rate was 23.1% (738/3196) and per embryo transfer it was 26.7% (738/2766), with a miscarriage rate of 3.4% (95/2766) per embryo transfer or 9.5% (95/997) per positive HCG. Among the 732 elective single embryo transfers (eSET), the rate of positive HCG was 38.0% and the clinical pregnancy rate was 29.6%, suggesting that eSET is a valuable option in routine assisted reproduction. Although minor differences were observed between countries, the follitropin alpha FbM pre-filled pen proved clinically effective, was generally well tolerated, and both the women and nurses/midwives found the training easy.