Introduction: Infertility has been recognized by the World Health Organization (WHO) since 2012 as a disease and a public health problem, and can be caused by several factors, both female and/or male. In almost half of the cases of infertility, there is at least one associated male factor. Several causes can generate seminal alterations, including drugs, alcohol, quality of life and even the man's age. Objectives: To evaluate the influence of the man's age and the year of collection of the test on the various seminal parameters of men investigated for conjugal infertility. To observe the influence of two criteria for classifying normality for referring the man for specialized evaluation. Methods: A retrospective descriptive study will be carried out to describe and compare the variation in seminal parameters before and after sperm capacitation in men who underwent sperm analysis at the Hospital da Mulher Prof. Dr. José Aristodemo Pinotti CAISM/UNICAMP from January 1989 to December 2023. This will allow approximately 36,000 tests to be analyzed. Statistical analysis: First, a descriptive statistical analysis of the data will be performed and the spermogram results will be categorized into three groups: altered (any parameter with values ​​below the WHO 2021 normal limits); intermediate (any parameter with values ​​above the WHO 2021 normal limits, but below the WHO 2010 normal limits); normal (all parameters with values ​​above the WHO 2010 normal limits). Subsequently, to test the influence of age on each of the spermogram parameters both before and after sperm capacitation, the tests will be categorized into age groups and the ANOVA or Kruskal-Wallis test will be performed depending on the normality of the data distribution. For semen parameters that are significantly related to age groups, linear regression will be performed to define the change point. To test the influence of the year of sperm collection on seminal parameters, polynomial regression will be performed for all tests and for tests categorized by age group. The significance level will be assumed at 5%. Excel files with all data generated in the research will be created. For reasons of secrecy and confidentiality, the data cannot be made available. For questions and possible reuse of the data, contact the authors by email.