We routinely use Vitrification Technique to rapidly freeze Blastocysts for all our Patients.
When you come back for your Embryo Transfer , we thaw 1 blastocyst at a time, and then transfer this back to your uterus.
Thawing and transferring just 1 blastocyst allows us to extend the number of
chances that you have to get pregnant with just one fresh Egg Collection and
ICSI/IVF procedure. This increases your cumulative conception rate, and
maximize your chances of getting pregnant.
Freezing (Vitrifying ) Blastoycsts are often considered
challenging due to their Size, Structure and presence of Blastocoelic Cavity.
We have been vitrifying Blastocysts for many years now , and
we routinely get a 100% Survival rate when we thaw them
When we freeze, the Expanded blastocysts are artificially
collapsed using a laser pulse , to remove water from the blastocyst. This dehydration
process is important as it Eliminates the risk of ice crystal formation
completely, which can harm the cells .
Hence , when we vitrify the blastocysts , they are usually in
a collapsed state during cryostorage . When we thaw them, they remain collapsed
during the thawing process and then slowly re-expand with few hours of
incubation post thaw.
As you can see in the picture, the blastocyst which was fully
expanded before freezing, was artificially collapsed before being vitrified. It
remained collapsed post thawing . We then allowed it to remain in culture in
the incubator at 37 C. During this time,
it expanded back fully after a few hours of incubation. The re expansion
usually takes about 1 hour. but usually the blastocysts are incubated for 3-4
hours before transferring them, to allow them to recover from the process of
thawing.
The fact that the blastocyst has re-expanded is convincing
proof that these cells and viable, and this is a healthy blastocyst, which has
a good chance of implanting. Today, sadly many clinics fool patients by
transferring blastocysts which have died after the thaw. Please don’t let your
doctor fool you !