Comparison of the cryopreservation method for day 3 embryos using slow freezing or vitrification
| ISRCTN | ISRCTN16672665 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN16672665 |
| Protocol serial number | N/A |
| Sponsor | Research Foundation Flanders (Belgium) |
| Funder | University Hospital Brussels (Universitair Ziekenhuis Brussel [UZ Brussel]) (Belgium) - covering incidental costs |
- Submission date
- 19/11/2008
- Registration date
- 30/01/2009
- Last edited
- 30/01/2009
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Pregnancy and Childbirth
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year
Plain English summary of protocol
Not provided at time of registration
Contact information
Mrs Lisbet Van Landuyt
Scientific
Scientific
UZBrussel
Centre for Reproductive Medicine
Laarbeeklaan 101
Brussels
1090
Belgium
| Phone | +32 (0)2 477 6698 |
|---|---|
| lisbet.vanlanduyt@uzbrussel.be |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Double-blinded prospectively randomised trial |
| Secondary study design | Randomised controlled trial |
| Study type | Participant information sheet |
| Scientific title | Randomised controlled trial comparing the implantation potential of a frozen-thawed cleavage-stage embryo cryopreserved using vitrification or slow freezing |
| Study objectives | To avoid multiple pregnancies, the proportion of elective single embryo transfers (SET) has increased substantially in our centre. Consequently, the impact of the cryopreservation program on the in vitro fertilisation (IVF)/intra-cytoplasmic sperm injection (ICSI) success rate is augmented since more surplus embryos become available. SET requires a cryopreservation program which optimally preserves the vitality of the surplus embryos. The first step to improve the efficiency of a cryopreservation program is to improve the post-thaw embryo survival. Retrospective analysis of our slow-cooling and thawing cryopreservation program showed that about 35% of day 3 cleavage stage embryos are severely damaged after freezing and thawing and are not suitable for transfer and another 15% is moderately damaged. According to recent findings, vitrification as a new cryopreservation method is assumed to reduce cryo-damage and thus better preserves the embryo viability. During vitrification the formation of intracellular ice formation is prevented by short incubation of the embryos in high concentrations of cryoprotective agents. Successful vitrification of embryos at all preimplantation stages has been reported. Retrospective analyses show higher or similar survival and implantation rates after vitrification compared to the results obtained after traditional slow freezing and thawing. However, these data remain unvalidated in prospectively randomised studies. The aim of the study is to compare the live birth rate after transfer of one frozen-thawed day 3 embryo using either vitrification or slow freezing as the cryopreservation method. |
| Ethics approval(s) | Medical Ethics Committee UZ Brussel-VUB gave approval on the 6th November 2008 (ref: B.U.N B14320084732) |
| Health condition(s) or problem(s) studied | In vitro fertilisation |
| Intervention | IVF patients will receive a frozen-thawed embryo that was frozen using the vitrification method or the standard slow freezing method. |
| Intervention type | Other |
| Primary outcome measure(s) |
Live birth rate per frozen-thawed embryo |
| Key secondary outcome measure(s) |
1. Post-thaw survival of thawed embryos (the percentage of intact blastomeres on the total number of blastomeres present before freezing) |
| Completion date | 01/12/2010 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Sex | Female |
| Target sample size at registration | 306 |
| Key inclusion criteria | 1. Female aged less than 38 years 2. Patients with day 3 single or double embryo transfer and surplus embryos frozen 3. Cryopreservation criteria: 3.1. 6 - 7 cell embryos on day 3 with less than or equal to 20% fragmentation 3.2. Greater than or equal to 8 cell embryos on day 3 with less than or equal to 50% fragmentation 3.3. No multi-nucleated embryos |
| Key exclusion criteria | Patients with preimplantation genetic diagnosis treatment |
| Date of first enrolment | 01/12/2008 |
| Date of final enrolment | 01/12/2010 |
Locations
Countries of recruitment
- Belgium
Study participating centre
UZBrussel
Brussels
1090
Belgium
1090
Belgium
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|---|
| IPD sharing plan summary | Not provided at time of registration |
| IPD sharing plan |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
