An evaluation of the use and handling errors of currently available recombinant human follicle-stimulating hormone pen injectors by women with infertility and fertility nurses. 
Background: This study compared preference ratings of women with infertility and nurses before and after simulated injection, and handling errors, with the GONAL-f®, Bemfola®, Ovaleap® and Rekovelle® pen injectors.  Research design and methods: Injector-naïve women and injector-experienced fertility nurses tested injectors with masked labels in a randomized testing order.  Injections were made into a foam pad and injectors were rated before and after use.  Handling errors were recorded during the study.  Ratings and errors were compared between pen injectors using ordinal or Poisson linear mixed models adjusted for testing order.  Results: 120 women and 60 nurses participated.  All participants tested GONAL-f and Bemfola injectors.  Because of their similarity, participants tested either Rekovelle (71 women; 30 nurses) or Ovaleap (49 women; 30 nurses) injectors.  The ratings from women were higher for GONAL-f vs other injectors after simulated use (p < 0.001 for all comparisons).  Fertility nurses rated GONAL-f injector higher than other injectors both before and after use (p < 0.01 for all comparisons).  Adjusted rates of total handling errors were lower with the GONAL-f vs other injectors (p < 0.001 for all comparisons) for both groups.  Conclusions: GONAL-f injector was rated significantly higher than other injectors, which may be related to less handling errors observed with the GONAL-f injector.