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Comparison of the probability of live birth after elective freezing of all embryos versus standard fresh embryo transfer in patients undergoing in-vitro fertilisation (IVF)

Fresh vs. Elective Frozen Embryo Transfer after IVF: a randomised controlled trial

Status
Not yet recruiting
Phases
Phase 4
Study type
Interventional
Source
ANZCTR
Registry ID
ACTRN12616000643471
Acronym
FAST
Enrollment
400
Registered
2016-05-18
Start date
2016-05-27
Completion date
Unknown
Last updated
2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

This study will test whether freezing all good or top quality day 5-6 embryos after IVF and subsequently thawing and transferring the best day 5-6 embryo into a natural or artificially prepared cycle leads to an increase in the probability of delivering a live baby from 35% to 50% as compared to the standard strategy of treatment which includes transferring the best quality day 5-6 embryo fresh and cryopreserving the remaining good or top quality embryos.

Interventions

Triggering of final oocyte maturation will be performed in the freeze-all arm with a bolus subcutaneous injection of 2 mg of leuprolide acetate when at least three follicles equal to or greater than 17mm in mean diameter are present at ultrasound. Oocyte retrieval will be performed at 34-36h after leuprolide administration. Embryos will be cultured for 5 days using the standard protocol of each clinic. All day 5 embryos of top and good quality (at least at early blastocyst stage and of ICM/Troph

Triggering of final oocyte maturation will be performed in the freeze-all arm with a bolus subcutaneous injection of 2 mg of leuprolide acetate when at least three follicles equal to or greater than 17mm in mean diameter are present at ultrasound. Oocyte retrieval will be performed at 34-36h after leuprolide administration. Embryos will be cultured for 5 days using the standard protocol of each clinic. All day 5 embryos of top and good quality (at least at early blastocyst stage and of ICM/Trophectoderm: AA, AB, BA, BB) will be cryopreserved using the method of vitrification. If only one embryo is available, this embryo will be vitrified regardless of quality as long as full embryo compaction has occurred. Delayed embryos will be allowed to be vitrified on day 6 as long as they fulfill the quality criteria (at least at early blastocyst stage and of ICM/Trophectoderm: AA, AB, BA, BB). Prior to freezing of embryos the developmental stage and quality of the blastocysts will be recorded (based on the judgement of the embryologist). Each blastocyst will be frozen in it’s own straw. Based on the pre-vitrification morphological quality, the best blastocyst will be thawed for the next embryo transfer. If the blastocyst does not survive, the next best blastocyst (based again on the pre-vitrification morphological criteria) will be thawed. The maximum period of embryo cryopreservation is theoretically indefinite, however it rarely exceeds five years. For the primary outcome of this study, the embryo cryopreservation period is estimated between 20 days-3 months. Hence, thawing and embryo transfer is expected to occur within this timeframe. Vitrification will be performed according to established local laboratory protocols with the use of TGA approved Vitrification solutions (Vitrolife or Sage). Vitrification will be performed at either 37 degrees Celsius or room temperature.

Sponsors

IVFAustralia Pty L.t.d.
Lead SponsorCommercial sector/Industry

Study design

Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Open (masking not used)

Eligibility

Sex/Gender
All
Age
18 Years to 39 Years
Healthy volunteers
No

Inclusion criteria

1) Indication for COS and IVF or ICSI with autologous gametes 2) Age: 18-39 years 3) BMI: 18-32 kg/m2 4) Presence of both ovaries 5) Normal menstruating cycles: 21-35 days 6) Cycle where prevention of premature LH rise is achieved using a GnRH antagonist 7) 8-19 follicles equal to or greater than 10mm in mean diameter on the day of triggering

Exclusion criteria

1) Endometriosis Stage>II 2) Indication for PGD/PGS 3) History of OHSS 4) Previous participation in the RCT 5) >3 previous unsuccessful stimulated cycles 6) History of hypothalamic dysfunction or history of inadequate pituitary response to GnRH agonist triggering

Outcome results

None listed

Source: ANZCTR · Data processed: Feb 4, 2026