A blastocyst transfer refers to an embryo transfer on day 5 or day 6, which is done to increase pregnancy rate and reduce the chance of multiple pregnancies.

An embryo goes through different stages as it develops from the fertilized egg (oocyte) until it hatches and attaches to the endometrial lining to achieve a pregnancy. A normal pattern of embryo division states:

  • 2-4-cell stage on day 2
  • 6-8-cell stage on day 3
  • 14-32 cell stage (called Morula) on day 4, with or without compacting
  • blastocyst on day 5

Unfortunately, not all embryos will develop to produce blastocysts in the laboratory. For example, embryos can stop developing at all stages and progress no further. Even if an embryo showed good developmental pattern on day 2 or day 3 that does not assure that this embryo will continue to develop to a good quality blastocyst on day 5. Depending on the age of the patients, only about 25 – 60% of embryos will reach blastocyst stage, so this selection method has the following advantages:

  • Improve the chance of pregnancy by selecting the best-developed embryos that have the best chance for implantation
  • Minimize the number of embryos transferred to reduce the risk of multiple pregnancy and its complications on both the embryos and the mother.

Moreover, not only the chances of getting pregnant increase significantly with a blastocyst transfer, but also the risk of having a miscarriage or an extrauterine pregnancy reduce significantly. This most probably happens due to the presence of more genetically normal embryos in blastocyst stage.

Blastocyst culture allows the embryologist and the IVF specialist to make objective decisions on which embryos are of good quality and suitable for transfer. Blastocyst culture is sensitive and delicate, the embryologists provide the embryos with the required media maintain suitable conditions, to obtain the highest possible rate of blastocyst.

Post Your Query