Determination of the ultrastructural pathology of human sperm by atomic force microscopy

Objective: To investigate ultrastructural changes, particularly at the surface, that occur in pathological spermatozoa by using atomic force microscopy (AFM) and to examine the morphological alterations responsible for infertile sperm. Design: Normal fertile and pathological spermatozoa were examined by using a conventional AFM in a noncontact mode. Setting: Andrology clinic at Los Andes University Hospital. Patient(s): Sperm of patients with oligoasthenoteratozoospermia (OAT) and asthenozoospermia were obtained from the Los Andes University Hospital, Mérida, Venezuela. Intervention(s): Main Outcome Measure(s): Morphological details, topological information, and three-dimensional images of the head, neck, and flagellum are presented for both normal and pathological sperm. Result(s): The obtained images clearly show dramatic alterations in the morphology of the head, neck, and flagellum of pathological sperm. Even the ultrastructure at the top of the flagellum and the region of the acrosome cap are clearly distinguishable. Conclusion(s): This study has significant importance not only for identifying spermatozoa alterations but also for understanding morphological defects and their effects on infertility. If properly exploited, this technique could be an important research tool.