Freeze All Strategy Versus Fresh Embryo Transfer After GnRH Analogue Trigger

Study Overview
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Brief Summary
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Ovarian hyperstimulation syndrome (OHSS) is one of the most dangerous complications of assisted reproduction technology (ART), described in approximatively 3 to 10% of stimulation cycles although an underestimation of the real incidence has been suggested. The use in clinical practice of GnRH antagonist has made it possible to perform the trigger with GnRH analogues, with the advantage of considerably reducing the risk of OHSS.

Detailed Description
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The main concerns about the trigger with analogue are about obstetric outcomes, since it may increase the Abortion Rate (AR) and reduce the Ongoing Pregnancy Rate (OPR) due to luteal phase deficiency, and on the other hand about oocyte quality and competence. While in order to maximize the chance of pregnancy at fresh embryo transfer after GnRHa trigger, several studies have focused on the importance of luteal phase support, other authors suggest that the best strategy is freeze-all: cryopreservation of all the obtained embryos and subsequent single embryo transfers. However, data about oocyte quality, retrieval rate, pregnancy rate and reduced occurrence of complications such as OHSS, especially on the very first embryo transfer, are still scarce.

Official Title
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Freeze All Strategy Versus Fresh Embryo Transfer After GnRH Analogue Trigger

Conditions
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Ovarian Hyperstimulation Syndrome, Pregnancy Related

Intervention / Treatment
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* Behavioral: obstetric outcomes after fresh versus cryopreserved embryo transfer


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing ART cycle with antagonist protocol stimulation and trigger with GnRH agonist patients are believed at risk of OHSS at time of trigger based on size and number of follicles developed (≥18 follicles with diameter 12 mm at induction). Exclusion Criteria: hypogonadotropic hypogonadism other ART protocols any patient that underwent freeze-all strategy in order to perform pre-implantation genetic testing (PGT) oncological or deferring motherhood freezing procedures

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| First fresh embryo transfer (group A)<br>The two groups analysed were defined according to the modality of first embryo transfer: cycles in which a fresh ET was performed at first, after a dual triggering or a rescue protocol (Group A) and cycles where a frozen-thawed ET was performed at first, after being chosen a freeze-all strategy (Group B). | Behavioral: obstetric outcomes after fresh versus cryopreserved embryo transfer<br>* measure of ongoing pregnancy rate, delivery rate, abortion rate, ectopic pregnancy rate, multiple birth rate, ovarian hyperstimulation syndrome incidence, drop out rate<br>|
| First cryopreserved embryo transfer (group B)<br>The two groups analysed were defined according to the modality of first embryo transfer: cycles in which a fresh ET was performed at first, after a dual triggering or a rescue protocol (Group A) and cycles where a frozen-thawed ET was performed at first, after being chosen a freeze-all strategy (Group B). | Behavioral: obstetric outcomes after fresh versus cryopreserved embryo transfer<br>* measure of ongoing pregnancy rate, delivery rate, abortion rate, ectopic pregnancy rate, multiple birth rate, ovarian hyperstimulation syndrome incidence, drop out rate<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ongoing pregnancy rate | number of viable pregnancies that had completed at least 12 weeks of gestation on the total number of ETs performed | 8 years | 
| delivery rate | number of deliveries of one or more live births over the total performed ET | 8 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Other pregnancy outcomes | ectopic pregnancy rate, miscarriage rate, multiple Birth Rate | 8 years | 
| Safety profile | Severe ovarian hyperstimulation syndrome incidence | 8 years | 
| the dropout rate | number of cycles in which any live birth (from either ART and/or spontaneous conceive) was not achieved and still some embryos or oocytes had to be thawed | 8 years |