Impact of male factors on morphokinetic parameters: a prospective analysis using time-lapse monitored embryos.

Introduction: Time-lapse technology enables recording embryo morphokinetic parameters, which are associated with embryonic competence and assisted reproductive technology (ART) outcomes. While female factors such as age and BMI are known to influence these parameters, the role of male factors remains understudied.

Aim: This study aimed to evaluate the influence of male factors on preimplantation embryo morphokinetics.

Methods: In this prospective observational study, 1,210 embryos from infertile couples undergoing Intracytoplasmic sperm injection (ICSI) or intracytoplasmic morphologically-selected sperm injection (IMSI) were monitored using time-lapse imaging. Male data, including age, BMI, sperm concentration, and sperm DNA fragmentation (SDF) were collected. Multiple regression analysis assessed the association between paternal factors and morphokinetic parameters, adjusting for female confounders.

Results: After adjustment, male age and BMI were found to significantly influence embryo developmental stages (from time to pronuclei appearance to t4 and t6 for age, from time to pronuclei appearance to t2 and t8 for BMI). The impact of sperm concentration was less consistent, and no significant relationship was observed with SDF.

Conclusions: These findings highlight the role of male factors, particularly age and BMI, in influencing embryo morphokinetics, even after accounting for female confounders. This underscores the potential for clinical interventions targeting paternal health to optimize ART outcomes. Additionally, the study reinforces the importance of considering both parental contributions in ART success, particularly the increasingly recognized influence of male age.