Can you do pgd on frozen blasts

Schedule an Appointment With Us. Liza Roscetti Meyer Nov 11 25 Comments. Reasons for wanting to test frozen blastocysts include: The patient has had a successful pregnancy and wishes to electively transfer a single embryo to avoid multiples. By screening the blastocysts prior to transfer, we improve the likelihood that a single embryo will implant.

Patients who have had a successful pregnancy and wish, for purposes of family balancing, to test the frozen embryos for gender before doing the transfer. Patients who have had an early miscarriage due to genetic abnormalities and wish to test their frozen embryos prior to transfer to decrease the chances of having to go through another pregnancy loss. Patients who have had multiple embryo transfers without a successful pregnancy.

By testing the embryos, it will give us additional information as to why implantation may not be successful and also help to pick the embryo most likely to create a viable pregnancy.

Patients who have only one blastocyst cryopreserved who wish to undergo a fresh cycle with pre-implantation genetic diagnosis PGD and add the one frozen embryo to that cohort. Nov Jul Feb This highly specialised form of genetic testing gives our patients the very best chance of conceiving - and taking home a baby. Wherever you are on your journey, one of our supportive nurses can help you understand your options and take the next step.

These conversations are free and informative. Skip to content. Genetically testing your embryos before transfer allows our scientists to select the very best ones, which boosts your chances of a successful pregnancy. Normal embryonic cells contain 46 chromosomes in 23 pairs - 23 chromosomes from each parent. If the egg or sperm has an extra or missing chromosome, the embryo created will have the same error.

This can lead to genetic conditions such as Down syndrome. Common questions What is genetic testing in IVF? The efficiency of the thaw, biopsy and refreeze technique was not significantly different to that of fresh cycles for rates of survival, results obtained and aneuploidy incidence.

Clinical pregnancy rates are not significantly different after the biopsy of fresh and previously cryopreserved embryos. The technique of preimplantation genetic testing for aneuploidies PGT-A enables the selection of chromosomally normal human embryos for replacement into the uterus Cinnioglu, The aim of PGT-A is to improve the methods of section of embryos for transfer and therefore decrease the time to live birth Kang et al.

Results obtained with PGS have improved markedly through the application of new technology for the analysis of biopsied samples Dahdouh et al. Next generation sequencing NGS is a powerful new technology that has enabled low- cost sequencing of entire genomes with increased sensitivity Fraguoli, However, the extended timeframe for NGS results weeks does preclude embryo transfer in the same cycle as embryo testing. Embryo cryopreservation techniques are therefore required.

Patients wishing to have PGT-A on previously cryopreserved embryos are currently limited from accessing this technique due to the requirement for refreezing of the embryos. Embryo cryopreservation techniques have, however, significantly improved in the recent years due the introduction of the vitrification method Yokota et al.

Although refreezing of human embryos with the vitrification method has been reported in the literature Yokota et al. Despite this, human refrozen embryos have been transferred to patients with successful outcomes Farhat et al. Previously, we and others have shown that the vitrification of human embryos after slow-thawing is practical for analysis with PGT-A Grifo et al.

In this report, we compare the results obtained from embryos thawed, biopsied and refrozen TBR with embryos biopsied for PGT-A without a prior freeze. The results show that the use of the thaw, biopsy and refreeze technique gives comparable results to PGT-A on fresh embryos and demonstrate that the technique is suitable for general use in the laboratory of assisted reproduction.

The study is a proof of concept retrospective analysis of results obtained from patients attending Create fertility between and Patients elected to have a cycle of assisted reproduction with PGT-A testing of freshly produced embryos, or with previously cryopreserved embryos.

All patients were counselled and signed informed consent for the procedures reported in this work. Furthermore, the refreeze technique has been previously published Grifo et al.

Patients were attending Create fertility, St Pauls, London for assisted reproduction treatment. Patients were prepared using standard controlled mild ovarian hyperstimulation protocols including ovarian stimulation with exogenous FSH Bemfola, Gedeon Richter, Budapest, Hungary and prevention of premature ovulation with a GnRH antagonist Cetrotidex acetate, Merck, Netherlands.

A single member of the medical staff co-ordinated all stimulation protocols, ensuring standardisation. All oocytes in the present project were treated with standard insemination techniques 3 hours after oocyte retrieval 60 minutes after removal of the cumulus complex. A single team of biologists co- ordinated all biological work, ensuring that both culture protocols and embryo assessment were standardised.

Zygote quality was scored hours after ICSI. Embryo quality on days 2 and 3 was assessed at 24 hour intervals after zygote assessment following Alpha scientist criteria Alpha scientists, , and embryo quality on days 5 and 6 were assessed using Gardner Criteria Gardner et al. Embryos were cryopreserved at the blastocyst stage, with a minimum quality 3CC as assessed using Gardner criteria Gardner et al.

Embryos were biopsied to remove a sample of the trophectoderm McArthur et al. Embryos defined as euploid by the PGT-A technique were selected for embryo transfer in a frozen embryo transfer cycle. Estradiol valerate Progynova, Bayer, Germany was administered to enable development of the uterus, followed by the administration of progesterone Cyclogest, Collins and Co, UK to initiate the luteal phase.

Embryos were thawed 5 days after the administration of progesterone and transferred on the same day. Embryo transfer followed standard protocols. The implantation rate was calculated by the observation of foetal heart beats after ultrasound analysis, 8 weeks after the establishment of pregnancy. Regression lines were calculated by the method of least squares and the significance of the regression lines was tested with the Pearson product-moment test. The z-test with Yates correction was used to test the significance of proportions where necessary.

During the same time-period, a further patients were treated with standard PGT-A protocols including biopsy of fresh blastocysts and cryopreservation post biopsy Group B. Maternal ages were not significantly different between group A In group A, a total of embryos were thawed for biopsy.

These included a total of 82 cleavage stage embryos and blastocysts. In group B, a total of blastocysts were biopsied from a total of fertilised eggs The blastocyst formation and recuperation rates in group A compare favourably with blastocyst development rates in group B. In group A, a total of embryos have been analysed at the present time. Of these embryos, a total of 31 embryos were noted to be euploid after biopsy A further 77 embryos were aneuploid These data compared favourably with group B, where embryos have been analysed up until the present time.

Here, 76 embryos were determined to be euploid after PGT-A