The RNA expression level of each gene in samples left on the transfer catheters

Samples left on the transfer catheter after cleavage stage embryos transfer (day 3, D3, presumable pre-receptivity, n=96) and blastocysts transfer (day 5, D5, presumable receptivity, n=127) in 223 ART patients who achieved successful clinical pregnancies subsequently were collected. The RNA expression level of each gene was estimated by FPKM (fragments per kilobase million).