Triggering Ovulation at Follicle Size Smaller or Larger Than 17mm in a Modified Natural Cycle
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Trigger at smaller folicular size.
- Who it may be relevant to
- Registry conditions: Embryo Transfer. Basic parameters: 18 years — 50 years · Female.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Spain
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Overview
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
- Procedure Trigger at smaller folicular size
Trigger indicated at folicular diameter smaller than standard clinical practice, from 13mm to 16.9mm
Primary outcome measures
- Pregnancy rate [Time frame: From embryo transfer up to 2 weeks later]
Secondary outcome measures (3)
- Implantation rate [Time frame: up to 8 weeks of gestational age]
- Cancelation rate [Time frame: Perioperative/Periprocedural]
- Miscarriage rate [Time frame: From embryo transfer to delivery, up to 40 weeks]
Eligibility criteria
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
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Open label
- Primary purpose
- Treatment
Study locations
Spain · 1 center
- Vida Recoletas Sevilla — Seville
Identifiers
NCT: NCT07088952 · 2310-SEV-02-MF