Infertility: Assessments of embryo transfer after in-vitro fertilization: effects of glyceryl trinitrate

The role of embryo transfer and its associated difficultieson the outcome of human in-vitro fertilization (IVF) were examinedusing a standardized procedure and a scoring system (embryotransfer scores 1–5). This system was used to assess anyeffects of the smooth muscle relaxant glyceryl trinitrate (GTN)on embryo transfer. Patients (n = 120) were randomized in adouble-blind manner at their first embryo transfer to receivesublingual GTN or placebo before the transfer. Retrospectiveanalysis showed that higher pregnancy rates were associatedwith uncomplicated transfers (score 1; P < 0.01). The outcomemeasures included pregnancy rate, total time of cervical manipulation(embryo transfer time) and embryo transfer score. All pregnancieshad a transfer score of 1 or 2, but no recorded parameter differentiatedbetween pregnant or non-pregnant cycles, and GTN had no significanteffect on any parameter.