Variability in the morphologic assessment of human sperm: use of the strict criteria recommended by the World Health Organization in 2010

Abstract

Objective: To determine the variability in the recognition of normal sperm and various sperm defects using the strict criteria recommended by the World Health Organization (5th edition, 2010).

Design: Sperm morphologic assessment by three experienced evaluators.

Setting: Image processing laboratory and reproduction research institute.

Patient(s): Semen donors from a sperm bank.

Intervention(s): The morphology of 5,296 sperm was evaluated using statistical analyses of variability.

Main outcome measure(s): The proportion and coefficients of variation (CVs) of normal sperm, defects of specific parts, and the categories of defects were measured. The degree of agreement between any two of the three evaluators was calculated. The multiple anomalies index, teratozoospermia index, sperm deformity index, and the CVs were also measured.

Result(s): The CVs of normal sperm, multiple anomalies index, teratozoospermia index, and sperm deformity index were 4.80%, 4.14%, 5.75%, and 6.81%, respectively. A broader range (4.80%-132.97%) of CVs was observed for the recognition of various defects. The coefficients of the degree of agreement concerning specific morphologic parts of sperm varied (0.387-0.607), with lower relative values for the head and mid-piece than for the tail and cytoplasm.

Conclusion(s): The sperm head is more difficult to evaluate than the other parts using the criteria recommended by the World Health Organization in 2010. The degree of agreement concerning specific parts and various defects varied in broad ranges. A stricter definition for each defect is needed.

Keywords: Sperm morphology assessment; agreement analysis; evaluation variability.