At Bubtree and Monash IVF we routinely transfer embryos that have reached the blastocyst stage of development. This means that your embryo transfer will usually happen five days after the egg collection procedure. The blastocyst is the stage of embryo development that usually occurs after embryos have been cultured in a laboratory for five days, by which time the embryo has started to divide into the parts that will ultimately form the baby (foetus) and those that will form the placenta. A blastocyst is composed of a sphere of cells with inner and outer layers that surround a fluid filled cavity. The outer layer of cells, called the trophectoderm, will ultimately give rise to the placenta and the inner group of cells (the inner cell mass) will develop into the foetus (baby). As the blastocyst continues to develop, the embryo expands, its shell thins and the final stage of blastocyst development is where it hatches out of its shell.
If a blastocyst is going to implant into the uterine lining, it will probably do so between one and four days after being transferred into the uterus (womb). Because the pregnancy potential of a blastocyst is higher than that of earlier stages of embryo development we are usually able to transfer a single embryo, and so minimize the chance of a multiple pregnancy.
At Bubtree and Monash IVF there is no extra charge for having a blastocyst transfer.
For more details on the stages and quality of embryo development please visit our webpage or ask for a copy of our fact sheet.