JBRA Assisted Reproduction 2025;29(Suppl.2 SBRA 2025):57
Poster Presentation
29^th Annual Congress of the SBRA. São Paulo/SP - Brazil, 2025
doi: 10.5935/1518-0557.20263596

P-45. Comparison of Blastulation Rate Between Group Culture and Individual Culture

Jonathan Boncristiano¹, Emilio Costa Garavini², Bernardo Rodrigues Moura³, Izaac Ferreira Oliveira Neto¹, Carolina Pinhol Vieira⁴

¹ Gerar In Vitro - Vitoria da Conquista - BA - Brasil
² Gerar In Vitro - Ponte Nova - MG - Brasil
³ Gerar In Vitro - Belo Horizonte - MG - Brasil ⁴ Gerar In Vitro - Montes Claros - MG - Brasil

Objective: To compare the blastulation rate between grouped embryo culture and individual embryo culture.
Methods: A total of 307 patients underwent group culture, with 2 to 4 embryos per drop, and 428 individual culture cycles were analyzed in a human reproduction clinic. The blastulation rate was compared between embryos cultured in group and individually, using the Mann-Whitney U test for statistical analysis. The null hypothesis assumed that both culture types have the same blastulation rate, while the alternative hypothesis proposed that the rates differ between the groups. To broaden the analysis, the blastulation rate was stratified into three age groups: ≤ 25 years, 26–35 years, and 36–37 years.
Results: The mean blastulation rate in the group culture was 33.3% (interquartile range [IQR]: 0.0%–50.0%), while in the individual culture group, the median was 25.0% (IQR: 0.0%–53.3%). Statistical comparison using the Mann-Whitney U test revealed no statistically significant difference between the groups (p=0.2397). In the ≤25 years age group, the mean blastulation rate was 50.0% in group culture (IQR: 0.0%–57.1%; n=21) and 20.0% in individual culture (IQR: 0.0%–45.5%; n=26). Despite the apparent difference between the means, the small number of patients and the high internal variability prevented the Mann– Whitney U test from detecting statistical significance (p=0.278). Interestingly, there was no significant difference between the groups, thus more studies are required to clarify these results. Among patients aged 26 to 35 years, the median blastulation rates were similar: 28.6% for group culture (IQR: 0.0%–50.0%; n=228) and 28.6% for individual culture (IQR: 0.0%–54.5%; n=314), with no statistically significant difference (p=0.669). In the 36–37 age group, the mean blastulation rate was significantly higher in group culture (31.0%; IQR: 11.1%–55.9%; n=48) compared to individual culture (14.8%; IQR: 0.0%–42.9%; n=82; p=0.0276).
Conclusion: This study provides evidence that embryo culture strategy may play a decisive role in patients of advanced maternal age (36–37 years), with group culture yielding significantly higher blastulation rates compared to individual culture. In younger age groups, the absence of relevant differences suggests that culture type may be selected based on other laboratory or logistical considerations. These findings have direct implications for assisted reproduction laboratory practice, supporting a more personalized approach to culture strategy according to patient profile. By aligning embryo culture protocols with maternal age, clinics may optimize clinical outcomes and resource management. Further research with larger sample sizes is warranted to validate these results and explore their potential integration into routine laboratory guidelines.