Sperm morphology: unstained and stained smears in fertile and infertile men

Two semen specimens from 34 fertile donors and 82 male partners of infertile couples were evaluated for semen quality. Sperm morphology was evaluated with unstained specimens and following Papanicolaou staining. A significant difference (p less than 0.001) was found in the percentage of morphologically normal spermatozoa in stained and unstained semen smears. Fertile semen donors had a significantly (p less than 0.001) higher percentage of normal sperm than men of unproven fertility. When compared to the fertile donors, 78% of the infertile men had increased teratospermia. Papanicolaou staining appears to enhance sperm morphology and allow improved discrimination of sperm head abnormalities.