Association between sperm morphology and embryo cleavage rate in in vitro fertilization: a retrospective study

Introduction. Infertility is a major reproductive health problem, and in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI) is widely used to improve conception in infertile couples. Embryo cleavage rate is an important laboratory indicator of early embryo development, while sperm morphology may reflect sperm structural and genetic integrity.

Aim: to analyze the association between sperm morphology and embryo cleavage rate in patients undergoing IVF/ICSI.

Materials and Methods. This analytical retrospective study used medical records of infertile couples undergoing IVF/ICSI at Dr. Hasan Sadikin Central General Hospital (Bandung) from January 2020 to December 2024. Patients with complete semen analysis based on World Health Organization (WHO) 2021 criteria and embryo development data up to day 2 post-fertilization were included. Sperm morphology was classified as normospermia or teratozoospermia, and cleavage rate as rapid, normal, or slow. Statistical analysis was performed using the Chi-square test, with odds ratios (ORs) and 95 % confidence intervals (CIs).

Results. A total of 159 records were analyzed. Sperm morphology was significantly associated with cleavage rate (p = 0.001). Teratozoospermia was found in 97.0 % of rapid cleavage cases, 47.3 % of normal cleavage cases, and 93.9 % of slow cleavage cases. Teratozoospermia was associated with higher odds of rapid cleavage (OR = 35.636; 95 % CI = 4.673–271.760) and slow cleavage (OR = 17.261; 95 % CI = 3.903–76.340).

Conclusion. Sperm morphology is significantly associated with embryo cleavage rate in IVF/ICSI. Teratozoospermia may be related to altered timing of early embryo cleavage and may serve as an additional prognostic parameter in IVF/ICSI counseling and laboratory assessment.

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