(212) The Questionable Clinical Utility of Sperm Morphology: Rate of Isolated Teratospermia in a Population of Fertile Men
Authors: Cheng L , Miller D , Wecht A , Pelzman D , Hwang K 
Published: March 2024

Introduction

Over the last several decades, sperm morphology has represented a standard component of semen analysis. However, its clinical utility is not well-defined, despite continual efforts by the WHO to address critiques of semen morphology criteria through increasingly strict guidelines. Issues with intra- and inter-laboratory technical variability, in addition to the subjective nature of the morphology assessment, have been thoroughly discussed in existing literature. Furthermore, current literature has highlighted the low predictive value of sperm morphology abnormalities in assisted fertility treatment (ART) and natural pregnancy outcomes. As of 2020, the American Society for Reproductive Medicine (ASRM) guidelines have noted that morphology alone is not highly predictive or diagnostic of infertility. However, past survey studies have demonstrated the pervasive belief among physicians of the value of sperm morphology, potentially leading to counseling patients towards more expensive ART methods. These concerns call into question the emphasis placed on sperm morphology assessment and its value in the clinical setting.

Objective

To better understand the impact of sperm morphology on fertility, we assessed sperm morphology in a population of known fertile men.

Methods

Healthy men over 18 years of age were recruited to provide one semen sample prior to vasectomy from March 2020 through November 2022. Inclusion criteria for the study was as follows: (1) patients were required to have biological children under the age of 5 years old, with no history of difficulty achieving pregnancy, and (2) had undergone no prior fertility procedures. Sperm morphology was analyzed using Papanicolaou stain with Kruger strict criteria by two technicians in an Andrology specialty laboratory per the WHO 5th edition manual.

Results

There were 83 men who participated in the study, 68 of whom (81.9%) had a complete sperm morphology assessment available. On average, participants were 37 years of age and had a mean BMI of 28 (22.8, 33.2). Of those with a smoking history available (n=61), 38 (62.3%) were non-smokers, 7 (11.5%) were former smokers, and 16 (26.2%) were current smokers. Patients had an average of 3 children with a mean youngest child age of 11.5 months old. There were 38 patients (55.9%) with 3% or lower normal sperm morphology, including two patients who had 0% normal morphology (Table 1). The most common morphologic abnormalities were head shape defects (n=59, 84.3%), followed by coiled tails (n=14, 20.3). Men 3% or lower normal sperm morphology were four times as likely to have both head and tail abnormalities than men with 4% or greater normal sperm morphology (n=8 vs n=2, respectively); half of these men also had lower than normal motility, whereas none of the men with 4% or greater normal sperm morphology had lower than normal motility.

Conclusions

More than half of fertile male patients (65.6%) had lower than normal sperm morphology in our study. The results of our study further question the clinical relevance of sperm morphology on fertility outcomes and if the current approach in assessing morphology is too strict.

Disclosure

No.