Assisted reproductive technologies in Latin America: the Latin American Registry, 2021.

Research question: What are the trends and impact of new technologies on the effectiveness and safety of assisted reproductive technology (ART) performed in Latin America during 2021?

Design: This was a retrospective collection of cycle-based multinational data obtained from ART procedures performed by 204 accredited institutions in 16 countries.

Results: In total 127,351initiated cycles resulted in 20,032 deliveries and 22,708 births. ART utilization showed great variability, from 623.5 cycles/million inhabitants in Uruguay to fewer than 35 in Guatemala and El Salvador. The proportion of women aged ≥40 years increased to 35.8%, while that of women ≤34 years dropped to 23.9%. Nonetheless, the proportion of single-embryo transfers (SET) increased from 11.9% in the previous decade to 42.4% in 2021. Of 22,708 babies born, 76.8% were singletons, 22.3% twins and 1.0% triplets or more. Intracytoplasmic sperm injection represented 84.5% of fertilization techniques, and blastocyst transfer increased from 49.6% in 2016 to 79.3% in 2021. The delivery rate after fresh blastocyst elective SET was significantly higher than after the transfer of one frozen embryo from a freeze-all cycle (P < 0.0001). The number of aspirations leading to preimplantation genetic testing has increased 2.8 times in 5 years and significantly increased delivery rates/transfer at all ages, including in oocyte donation (P ≤ 0.002), and reduced miscarriage in women ≥35 years old. In oocyte donation, delivery rates after the fresh transfer of embryos from vitrified-warmed oocyte cycles generated similar outcomes to frozen embryo transfer. Perinatal mortality increased from 7.7‰ in singletons to 21.3‰ in twins.

Conclusion: The systematic collection of cycle-based multinational data contributes to cooperative sustained development and helps implement evidence-based reproductive decisions.