Urinary concentrations of phthalate and phthalate alternative metabolites and sperm DNA methylation: A multi-cohort and meta-analysis of men in preconception studies.

Phthalates are ubiquitous pollutants in the environment; however, the mechanisms of phthalate-associated reproductive disorders in men are not fully understood. The aim of this study is to investigate associations between urinary phthalate metabolite concentrations and sperm DNA methylation. The study was conducted on 697 men from three prospective pregnancy cohorts: Longitudinal Investigation of Fertility and the Environment (LIFE) Study, Sperm Environmental Epigenetics and Development Study (SEEDS), and Environment and Reproductive Health (EARTH) Study.

Mixtures of per- and polyfluoroalkyl substances (PFAS) alter sperm methylation and long-term reprogramming of offspring liver and fat transcriptome.

Male fertility has been declining worldwide especially in countries with high levels of endocrine disrupting chemicals (EDCs). Per- and polyfluorinated alkyl Substances (PFAS) have been classified as EDCs and have been linked to adverse male reproductive health. The mechanisms of these associations and their implications on offspring health remain unknown.

Associations between Sperm Epigenetic Age and Semen Parameters: An Evaluation of Clinical and Non-Clinical Cohorts.

The well-documented relationship between chronological age and the sperm methylome has allowed for the construction of epigenetic clocks that estimate the biological age of sperm based on DNA methylation, which we previously termed sperm epigenetic age (SEA). Our lab demonstrated that SEA is positively associated with the time taken to achieve pregnancy; however, its relationship with semen parameters is unknown. A total of 379 men from the Longitudinal Investigation of Fertility and Environment (LIFE) study, a non-clinical cohort, and 192 men seeking fertility treatment from the Sperm Environmental Epigenetics and Development Study (SEEDS) were included in the study.