From the age of 35, the number of eggs with chromosomal changes (aneuploidia) grows. At 40, up to 80% of embryos may have genetic errors that prevent implementation or cause abortions. THE Pre-implantal genetic diagnosis (PGT-A) makes it possible to analyze a small group of cells that will give rise to the placenta (on the fifth or sixth day of development), allowing only embryos with a number of normal chromosomes for transfer. Multicenter studies indicate that in women aged 38 to 42, the PGT-A:
• Good the live birth rate per transfer.
• Reduce up to 70% the risk of miscarriage.
• Remove The need to transfer more than one embryo, avoiding multiple pregnancies, which have additional risks.
PGT Indications and Safety
The procedure is recommended in the following cases:
• Advanced maternal age (≥ 38 years)
• History of repetition abortions or implementation failures in previous transfers
• Family known genetic diseases (in this case, PGT-M is indicated)
• Need to avoid aneuploidia in couples who have had a child
• When any of the country has structural changes in karyotype (PGT-SR is indicated)
Embryo biopsy is performed with laser or chemicals under precision microscopy and, in correct indications, does not significantly compromise the embryo development potential. Follow -up studies to childhood show absence of increased malformations or health problems related to the procedure. However, the technique requires certified laboratory, experienced embryologist and embryo freezing, as the result usually takes about two weeks.
Ethical and psychological aspects of the choice of the embryo
Analyzing embryos can provide relief from reducing uncertainties, but can also generate anxiety and dilemmas. Couples can find few viable embryos or have to decide on the fate of the altered embryos. Issues related to religious beliefs, discard or anonymous donation should be discussed before treatment. Accompanying a multidisciplinary team – doctors and psychologists – can help:
• Understand test limitations (it does not guarantee a “perfect” baby; detects only some of the possible changes);
• Prepare the couple for unexpected results (like no embryo fit for transfer);
• Avoid false expectations of absolute success: even with normal embryos, uterine or immunological factors can influence the implementation and development of pregnancy.
FINAL CONSIDERATIONS
For couples with adequate indication, embryonic biopsy can reduce time until reproductive success, minimizing physical, emotional and financial wear. The decision, however, should be made individually and, in many cases, accompanied by psychological counseling, to ensure that the process happens from a perspective of comprehensive care.
Dani Ejzenberg (CRM 100673)
Gynecologist and Assisted Reproduction Specialist – Nilo Frantz Clinic and member of Brazil Health
