Natalia Szlarb, MD, PhD
Gynaecologist & Fertility Specialist at UR Vistahermosa, UR Vistahermosa
Donor Eggs, Genetics PGS / PGT-A, IVF Abroad, Success Rates
The average IVF pregnancy rates for women over the age of 35 oscillate around 18% without PGT-A testing. With testing, however, the pregnancy rates shoot up to over 80%.As we said, however, not all patients have the ovarian reserve to produce enough high-quality eggs to even have multiple embryos in the blastocyst stage per cycle. As women grow older, the chances of those eggs being genetically abnormal also grow higher, which often results in failed IVF cycles or failed pregnancies. This is where egg donation programs come into play – they’re an efficient, pragmatic and safe solution. According to data, 93% of patients experience successful pregnancies by the third egg donation cycle. Safety is a major concern for patients who are considering such an approach. Dr Szlarb reassures us that egg donation has been tightly regulated by Spanish law since 1988. Donors go through various medical and psychological screenings, as well as phenotype analysis, to make sure that the donor matches the recipient as closely as possible on the genetic level, and that a child produced through this method will most closely resemble you and your partner. Following that, the patient fills out a phenotype questionnaire, where you describe yourselves and your background; this helps to narrow down the pool of donors to those who most closely match your answers. Finally, doctors then compare photographs of you and your potential donors, selecting around four of those who look the most like you. Finally, based on their schedules, a donation is arranged as quickly as feasible. As you can see, the process is heavily regulated, but that’s not all; Spanish law obligates clinics to perform a lot of low-level genetics work on the donors to make sure they aren’t carriers of any diseases that could be passed on to the child or that could be a danger to a patient who experiences immunological issues; in that case, it’s almost as tightly regulated as liver or kidney transplants. Simply put, the process is heavily regulated to ensure the safety of all parties involved. Following the donor selection and the fertilization of eggs, embryos are then developed to the blastocyst stage. As we mentioned earlier, this takes five days. On day five the embryos are frozen to allow for genetic testing; if the patient opts out of testing, there are still non-invasive monitoring methods, such as the time-lapse technology, which allows embryologists to select the embryo with the best cell division rates to be implanted. Freezing embryos for testing doesn’t affect the success rates – quite the opposite, in fact. Embryos aren’t the only ones to enjoy regular testing, however. The patient undergoes a uterine lining biopsy in order to determine the best time for implantation. This increases the chance of a successful pregnancy during the first transfer. This issue will be discussed during a future webinar, so stay tuned!