Fig. 1

Morphological abnormalities in sperm cells after intravesical BCG therapy. Representative Papanicolaou-stained images of sperm morphological defects observed after intravesical Bacillus Calmette-Guérin (BCG) therapy. a-c Short tail defect, b Bent neck defect, d Amorphous head defect. These abnormalities were identified using Kruger’s strict criteria