Study of Abnormally Fertilized Embryos
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: Parental samples, PGT-A, TE rebiopsies and spent blastocyst media collection.
- Who it may be relevant to
- Registry conditions: Infertility (IVF Patients). Basic parameters: 18 years — 49 years · All.
- 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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Official title
Prospective Observational Study of the Morphokinetics and Ploidy of Blastocysts With Abnormal Fertilization (1PN, 2.1PN and 3PN) to Identify the Origin of Fertilization Alterations
Overview
The goal of this observational study is to determine the diploidy rate of haploid and triploid embryos from in vitro fertilization (IVF) cycles. The main questions it aims to answer are: * Can a molecular genetic fertilization check of abnormally fertilized embryos be used to expand opportunities for couples undergoing assisted reproduction treatment? * Is the chromosomal loss or gain present in abnormally fertilized embryos predominantly maternal in origin? For this purpose, we will evaluate the morphokinetics and ploidy of about 300 embryos with different types of abnormal pronuclear patterns (1PN, 2.1PN, and 3PN) that reach the blastocyst stage. Whenever possible, embryos with a non-diploid chromosomal complement will also be assessed to determine the origin (maternal or paternal) of the chromosomal set that has been lost or gained. Study subjects will follow their previously scheduIed IVF/ICSI treatment and no additional visits/interventions will be required for participating.
Detailed description
Chromosomes are cellular structures containing the majority of the genetic information of a living organism. Gametes (oocytes and spermatozoa) contain only a single set of 23 chromosomes within structures known as pronuclei (PN). Upon fertilization, the 23 chromosomes from the oocyte and the 23 chromosomes from the sperm combine to form a 2PN zygote, which contains a total of 46 chromosomes.
In assisted reproduction (ART) laboratories, the embryologists can determine through morphological evaluation whether the fertilization process was normal (2PN) or abnormal (0PN, 1PN, or \>2PN). For an ART treatment, only a successfully fertilized oocyte (2PN) that develops to the blastocyst stage may be suitable for embryo transfer. However, previous studies have demonstrated that some embryos from oocytes with abnormal fertilization may possess a normal chromosomal content and could be used in ARTs when embryos from normal fertilization are not available.
There are genetic analysis techniques to determine not only if an embryo is euploid (contains a normal number of chromosomes) but also to assess if it is haploid, diploid or triploid (1PN, 2.1PN, and 3PN respectively). These techniques may be applied to "rescue" embryos with abnormal fertilization that are currently being discarded. This approach could be beneficial for IVF patients with a limited number of viable embryos available (diminished ovarian reserve cases, advanced maternal age, poor response to ovarian stimulation, etc.).
The current prospective and observational study has been approved by the competent Research Ethics Committee and every potential participant will be asked to sign the study informed consent.
The 300 embryos that will be part of the study will be recruited in the laboratory of the collaborating center on the day of fertilization after performing the conventional IVF procedures. Following these same routine procedures, biological samples from both parents will also be stored to perform the genetic analysis to determine the origin of the chromosomal anomalies. A biopsy will be taken from the selected embryos when they reach the blastocyst stage for the genetic analysis that will allow detecting whether there is indeed any chromosomal anomaly. All embryos not confirmed as chromosomally normal will be thawed, washed, and cultured for a second biopsy to confirm their previous diagnosis and the origin of the chromosomal abnormalities. For this new analysis, in addition to the biopsies, individual samples of the culture media of the thawed blastocysts will be collected and stored. Samples will be shipped to Igenomix for the genetic research and further data analysis.
The expected duration of the study is 18 months. Embryos will be included in the participating center for an estimated period of 13 months. Participants involvement in the study is just linked to the moment of the consent form signature. Exceptionally, embryos from abnormal fertilization that were informed as chromosomally normal after the first biopsy can be considered to transfer providing there are no other embryos available. If the patient decides to proceed with the transfer, her clinical follow-up will be part of the study until achieving ongoing pregnancy (12 gestational weeks). After that, her participation in the study will end but her physician will continue monitoring the pregnancy until delivery, if applicable, in accordance with the standard clinical practice.
Interventions
- Genetic Parental samples
On fertilization, following the conventional ICSI/IVF procedure, samples from cumulus cells (obtained during the routine oocyte denudation process) and surplus sperm cells present in seminal plasma will be retrieved. These samples will be stored frozen at -20°C until they are sent to Igenomix. There, they will be used to perform the genetic analysis required to achieve the study's objectives, provided the patient consents to participate. If the patient ultimately chooses not to participate, thes - Diagnostic test PGT-A
On day 3 of development, assisted hatching will be performed to facilitate biopsy at the blastocyst stage. Each embryo will be biopsied in the laboratory using conventional trophectoderm (TE) biopsy techniques on day +5, +6, or +7 of development, depending on when they reach the appropriate blastocyst stage. After biopsy, blastocyst will be vitrified following the clinical routine protocol and store until the genetic results are available. The biopsy samples will be placed in a PCR tube labeled - Genetic TE rebiopsies and spent blastocyst media collection
After obtaining the PGT-A results, any embryo not genetically confirmed as euploid and without ploidy abnormalities will be thawed, washed, and cultured for rebiopsy. A complementary analysis using next-generation sequencing (NGS) techniques will be performed to confirm the diagnosis and determine the origin of the abnormalities. For this additional analysis, in addition to the new biopsies, the individual culture medium of each embryo will be aspirated after an incubation period of 8 to 24 hour
Primary outcome measures
- Diploidy rate in haploid embryos from IVF/ICSI [Time frame: 3 months]
- Diploidy rate in triploid embryos from IVF/ICSI [Time frame: 3 months]
Secondary outcome measures (8)
- Origin of the chromosomal abnormalities in embryos with a non-diploid chromosomal content [Time frame: 6 months]
- Pregnancy rate of euploid embryos from abnormal fertilization [Time frame: 2 weeks after the embryo transfer]
- Implantation rate of euploid embryos from abnormal fertilization [Time frame: Up to 4 weeks after the embryo transfer]
- Biochemical pregnancy rate of euploid embryos from abnormal fertilization [Time frame: 4 weeks after the embryo transfer with euploid embryos from abnormal fertilization]
- Ectopic pregnancy rate of euploid embryos from abnormal fertilization [Time frame: 4-5 weeks after the embryo transfer]
- Clinical miscarriage rate of euploid embryos from abnormal fertilization [Time frame: Up to 12 gestational weeks]
- Ongoing pregnancy rate of euploid embryos from abnormal fertilization [Time frame: Over 12 gestational weeks]
- Voluntary termination rate of euploid embryos from abnormal fertilization [Time frame: Up to 12 gestational weeks]
Eligibility criteria
Inclusion criteria
- ART patients who sign the Informed Consent of the study.
- Age: oocytes from women ≤ 49 years and semen from men ≤ 60 years. Donation of gametes is allowed.
- ≥1 blastocysts from oocytes with an abnormal pronuclear pattern (1PN, 2.1PN, and/or 3PN) and with the presence of 2 polar bodies (PB), cultured in a time-lapse incubator.
Exclusion criteria
- No exclusion criteria have been considered for this study.
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Cohort
Study locations
Spain · 1 center
- Equipo Médico Crespo Valencia — Valencia
Identifiers
NCT: NCT06940973 · EJC-SAFE-24-02