Human Reproduction · 1994 · 134 citations · 0 references
Life SciencesDevelopmental BiologyGeneticsEmbryologyIn Vitro FertilizationReproductive BiologyEarly Embryonic DevelopmentEmbryo EvaluationEmbryonic GrowthPreimplantation Embryo DevelopmentSex DifferentiationEmbryology Of The Reproductive SystemEmbryonic Growth CurvesEmbryonic Growth DynamicsGrowth RatesPregnancy Outcome AssessmentY Chromosome Function
Growth rates of human preimplantation embryos fertilized in vitro were assessed and compared to the sex of the pregnancy outcome. The likelihood of a liveborn male was significantly greater than that of a female if the mean number of cells/embryo was four or greater at the scheduled time of transfer (odds ratio of 6:1). This finding suggested that the Y chromosome expresses factors which influence embryonic growth rates immediately after fertilization.