Sperm morphology indices as exploratory screening tools for elevated DNA fragmentation: a single-centre correlation...

Area of Science:

• Andrology
• Reproductive Medicine
• Semen Analysis

Background:

• Sperm morphology assessment is standard in semen analysis.
• The link between specific morphological indices and sperm DNA fragmentation (DFI) requires further clarification.
• This study investigates correlations between Teratozoospermia Index (TZI), Sperm Deformity Index (SDI), Multiple Anomalies Index (MAI), and DFI.

Purpose of the Study:

• To evaluate the correlation between TZI, SDI, and MAI with DFI.
• To derive exploratory thresholds for TZI, SDI, and MAI to identify men with DFI > 20%.

Main Methods:

• Retrospective analysis of 135 semen samples from men aged 20-55.
• Manual calculation of TZI, SDI, and MAI from Papanicolaou-stained smears.
• Measurement of DFI using the GC-SCD-20 kit.
• Pearson correlation and ROC analysis with Youden-optimised thresholds.

Main Results:

• Weak positive correlations were found between TZI, SDI, MAI, and DFI (r=0.263-0.371, p<0.001).
• ROC analysis showed modest discriminatory performance (AUC=0.620-0.680).
• Exploratory thresholds (TZI>1.85, SDI>2.42, MAI>2.53) achieved 82-90% sensitivity and 44-53% specificity.

Conclusions:

• TZI, SDI, and MAI show weak but significant correlations with DFI.
• These indices present a high-sensitivity, low-specificity screening profile for elevated DFI.
• Derived thresholds require prospective validation and should supplement, not replace, direct DFI testing.