Improvement of Fertilization Rates of In Vitro Cultured Human Embryos by Exposure to Sound Vibrations

Exposure of in vitro cultured human embryos to microvibrations can improve embryo development, but music as a source of mechanical vibrations has not yet been explored. To determine the effect of the exposure to music during in vitro culture, 967 oocytes (114 patients) were analyzed. Before insemination, oocytes from each patient were randomly assigned to two groups: embryo culture exposed to music (479 oocytes), and embryo culture without music (488 oocytes). Three different types of music were also tested: pop, heavy metal and classical. Fertilization rates and embryo quality (score, cleavage stage and multinucleation) were compared using a generalized linear mixed model (two levels were considered) and analyzed by means of Bayesian inferences using Integrated Nested Laplace (INLA). Results showed that fertilization rates were 4.82% higher when oocytes were exposed to music but no statistically significant differences were found regarding embryo quality on Day 2. Moreover, no statistically significant difference was observed between the different types of music played (pop, heavy metal and classical). As a conclusion, the routine use of music inside incubators during in vitro culture could be a useful tool to improve fertilization rates. The effect of music on embryo development up to Day 5 should be evaluated.