Dados do Trabalho

Title

Influence of maternal age on the blastocysts rate and implantation associated with the number of oocytes

Objective

Analyze maternal age related to the number of recovered oocytes as a prognosis factor directly associated with the results of in vitro fertilization treatments.

Methods

Was performed observational, retrospective and descriptive study was carried out, in which the medical records of patients who underwent In Vitro Fertilization (IVF) treatment during the period from January 2018 to September 2022 were evaluated, carried out at the InVentre Assisted Reproduction Clinic, located in Santo André in the state of São Paulo. The variables and proportions analyzed were: number of oocytes collected, mature oocytes, fertilization rate, number of blastocysts, number of transfers and implantation rate.

Results

150 autologous IVF cycles were evaluated. Three groups of different maternal ages were compared: up to 35 years old (67 cycles), 36-39 years old (50 cycles) and 40 years old or more (33 cycles).
No significant differences were found in the rates of mature oocytes and fertilization between the different groups.
The average number of oocytes recovered and of embryos that reached the blastocyst stage was significantly lower (P < 0.05) in the group of patients aged 40 years or older, when compared to the other two younger groups.
The implantation rate after embryo transfer (fresh or frozen-thawed cycle) was significantly higher (P < 0.05) in the groups of women who underwent treatment before 40 years of age. In the groups of patients up to 35 years old and 36-39 years old, the implantation rate was 68.5% and 52.4%, respectively, while in patients aged 40 years or more, this rate was 36%.
In addition, the existence of a high relationship between the number of oocytes and blastocysts was observed, so that for each 1 more oocyte produced by each patient, regardless of the group, there was a mean increase of 0.304 blastocysts (95% confidence interval).
Finally, it was observed that for every 1 more blastocyst available for transfer, the probability of implantation increased 1.198 times (95% confidence interval), while for every 1 year of age, this probability decreased 0.909 times (interval of 95% confidence).

Conclusion

In conclusion, the number of recovered oocytes, degree of maturation and fertilization rate did not show significant differences between the groups, however, based on the analyzed samples, the rate of embryos that reached the blastocyst stage and resulted in an implantation after embryo transfer was significantly lower in patients aged over 40 years. This idea reinforces that a woman's age is an important indicator of the success rate of assisted reproductive technology.

Keywords

Maternal age; Blastocysts; Oocytes; Implantation.