Single Step Protocol and Multi-step Warming Protocol for Blastocyst FET
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexFemale
Age18+
SponsorMỹ Đức Hospital
About this trial
The multi-step thawing protocol with a reduction of non-permeable cryoprotectant concentrations to reduce osmotic shock caused by the rapid influx of water. Recent studies have shown that a simplified warming protocol by only a thawing solution gave a comparable survival rate but increased pregnancy rate, reduced patients' waiting time, and decreased the workload of embryologists.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
Women aged from 18
Undergoing no more than 3 previous IVF/ICSI cycles
Had at least a single good-quality blastocyst frozen.
Endometrium preparation using artificial cycle
Disqualifiers
Embryos from cycles after in-vitro maturation, pre-implantation genetic testing (PGT)
Having contraindications for exogenous hormone administration (e.g., breast cancer, thromboembolic disease)
Having uterine abnormalities (e.g., adenomyosis, intrauterine adhesions, unicornuate/ bicornuate/ arcuate uterus; unremoved hydrosalpinx or endometrial polyp)
Trial design
Design model
Parallel
Treatments tested in this trial
Single-step warming protocol by thawing solution only
Procedure/SurgeryPotentially eligible patients' vitrified blastocysts will be thawed by a single-step thawing protocol. For the warming phase, vitrified blastocysts are exposed to the thawing solution of a commercial embryo thawing kit (Irvine Scientific Inc., USA) at 37°C for one minute. Immediately following this, embryos will be rinsed in a 35mm diameter dish of 2ml of pre-equilibrated thawing solution before being placed in culture media in the incubator for at least 2 hours before transfer.
Standard warming protocol
Procedure/SurgeryFor the MS protocol, thawing kits were equilibrated overnight in a 37°C incubator. Warming procedures utilized the kits (Cryotech RtU, Japan). To remove the cryoprotectants, blastocysts were warmed, and cryoprotectants were diluted in a three-step process. The warming process starts with the exposure of blastocysts to thaw solution (TS) with 1M trehalose for one minute at 37°C. Subsequently, the blastocyst will be transferred to a second well containing a dilution solution (DS) of 0.5M trehalose for a two-minute rinse at room temperature. This is followed by two additional three-minute and 30-second rinses in the wash solution (WS) at room temperature. The timeline for standard warming of blastocysts requires a total of 6.5 min. After thawing, embryo will be placed in the incubator at least 2 hours before transfer.
Treatment groups
816 Participants
are divided into 2 treatment groupsGroup A: Single-step thawing protocolExperimental treatment 1 intervention
Group B: Multi-step thawing protocolExperimental treatment 1 intervention
Trial outcomes
Primary outcomes
1
Live birth rate
Live birth is defined as the complete expulsion or extraction from a woman of a product of fertilization, after 22 completed weeks of gestational age; which, after such separation, breathes or shows any other evidence of life, such as heart beat, umbilical cord pulsation or definite movement of voluntary muscles, irrespective of whether the umbilical cord has been cut or the placenta is attached. A birth weight of 500 grams or more can be used if gestational age is unknown
Time frame
At 22 weeks of gestationSecondary outcomes
1
Survival rate
The survival rate by the presence of blastocoel re-expansion before embryo transfer.
Time frame
At least 2 hours after thawing.2
Cancellation rate
Cancellation due to: The blastocyst cells are lysed after thawing.
Time frame
Any day during endometrium preparation days before embryo transfer.3
Positive pregnancy test
Serum ß-hCG ≥25mIU/mL
Time frame
At 2 weeks after embryo placement4
Implantation rate
The implantation rate is explained as the number of gestational sacs per number of embryos transferred
Time frame
At 3 weeks after embryo placementSponsors and contacts
Click on the lead sponsor to view all of their trials.
Source ClinicalTrials.gov