Embryo Transfer
Conditions
Keywords
Natural Cycle, Frozen Embryo Transfer, Follicle Size, Pregnancy, Implantation
Brief summary
The rise in frozen embryo transfer (FET) cycles within assisted reproductive technology (ART) has sparked the need to refine endometrial preparation protocols. The switch from hormone replacement cycles (HRT) to natural cycles, poses scheduling challenges onto laboratories, doctors and patients. The modified natural cycle (mNC), offering more precision for scheduling, shows promise but lacks comprehensive data on the potential flexibility of triggering criteria that may allow to control timing in a wider range. This prospective randomized study seeks to address this knowledge gap by evaluating the non-inferiority of triggering ovulation in mNC with follicle diameters of 13-16.9mm compared to the conventional 17-22mm. The study aims to enhance the understanding of the impact of follicle size at ovulation in reproductive outcomes, optimize FET treatments providing a more flexible mNC protocol, and improve patient care in ART clinics.
Interventions
PROCEDURETrigger at smaller folicular size
Trigger indicated at folicular diameter smaller than standard clinical practice, from 13mm to 16.9mm
Sponsors
Vida Recoletas Sevilla
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Prospective open randomized parallel group 1:1 ratio
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 50 Years
Healthy volunteers
No
Inclusion criteria
* At least one expanded blastocyst (regardless of its quality) * Spontaneous menstrual cycles * Consent to undergo frozen embryo transfer in a modified natural cycle
Exclusion criteria
* Abnormal uterine cavity * Fluid in endometrial cavity
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Pregnancy rate | From embryo transfer up to 2 weeks later | Rate of positive pregnancies over total transfers performed, according to beta-test result |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Implantation rate | up to 8 weeks of gestational age | Implantation rate, defined as number of gestational sacs per embryos transferred |
| Cancelation rate | Perioperative/Periprocedural | Number of cancelled embryo transfers per initiated endometrial preparation cycles. Transfer canceling implies end of study. |
| Miscarriage rate | From embryo transfer to delivery, up to 40 weeks | Number of miscarriages of any type registered after transfer during the study, per total number of transfers performed |
Countries
Spain
Contacts
Primary ContactManuel Fernández Sánchez, MD PhD
Backup ContactClara Palacio de Marco, MSc
Outcome results
None listed