Dados do Trabalho

Title

Does the air temperature of IVF laboratory affect good quality blastocyst rate?

Objective

To evaluate the influence of IVF laboratory air temperature at the time of ICSI on embryo culture.

Methods

Retrospective study including all fresh ICSI cycles from January to June 2023. The temperature of the IVF laboratory was measured with a thermometer at the time of ICSI and the cycles were splitted in two temperature range groups: control (22-25.9ºC) and study (<22ºC or ≥26ºC). Mean age of patients, AMH (ng/mL) and the number of oocytes retrieved were assessed. The primary laboratory outcome compared was good quality blastocyst rate, and the secondary were: fertilization rate, good quality cleavage embryo rate, and blastulation rate. Statistical analysis was conducted by paired test with multiple linear regression, and results were considered significant when p<0.05.

Results

We included 97 ICSI cycles, enrolled into two groups: 66 were included in the control group (air temperature range of 22-25.9ºC) and 31 in the study group (lower than 22ºC [n=10] or higher than 26ºC [n=21]). There was no statistical difference for the mean age of patients [36.2 vs 35.9 (p=0.810)], AMH [2.83 vs 2.31 (p=0.359)] and number of oocytes retrieved [8.89 vs 9.64 (p=0.669)] for control and study groups respectively. Normal fertilization rate (2PN/2PB) was not statistically different [76.6% vs 78.6% (p=0.703)] between both groups, as well as D3 good quality embryo [57% vs 45.1% (p=0.062)] and blastulation rates [61.7% vs 48.5% (p=0.107)]. However, a statistical significant reduction of good quality blastocyst rate was observed when the temperature in the IVF laboratory at the time of ICSI. The study group presented a reduction 16.5% compared to the control group 44.9% [OR: 0.284 (0.108-0.460), p=0.002]. This result was confirmed by multiple linear regression, indicating that the only variable associated with good quality blastocyst rate was the IVF lab temperature (p=0.014).

Conclusion

The good quality blastocyst rate is greatly affected by the air temperature of the IVF laboratory at the time of ICSI, therefore temperatures lower than 22ºC and higher than 26ºC should be avoided.

Keywords

temperature, IVF, fertilization, blastulation, ICSI.