Phthalate metabolites in urine and follicular fluid in relation to menstrual cycle characteristics in women seeking fertility assistance.
Level 4 - case-series / case-control
Cross-sectional observational study nested in a clinical cohort
PubMed 38064925 · doi:10.1016/j.envint.2023.108362
What was done
Researchers measured eight phthalate metabolites in paired urine and follicular fluid samples from 441 women attending a fertility center in the Tongji Reproductive and Environmental (TREE) cohort using HPLC-MS/MS. Menstrual cycle characteristics were assessed via questionnaire. Multivariable linear regression, Poisson regression, and quantile g-computation were used to evaluate individual and joint pollutant associations with cycle parameters after covariate adjustment.
What was found
Per log10-unit increase in urinary mono(2-ethylhexyl) phthalate (MEHP), menstrual bleeding duration decreased by 0.20 days (95% CI: -0.37, -0.03). In follicular fluid, mono(2-ethyl-5-carboxypentyl) phthalate (MECPP) and total DEHP metabolites (∑DEHP) were inversely associated with cycle length (β = -1.92, 95% CI: -3.10 to -0.75 and β = -1.87, 95% CI: -3.56 to -0.19, respectively). Associations between phthalates and irregular cycle, dysmenorrhea, hypomenorrhea, or cycle length variation were generally null, as were overall phthalate mixture analyses.
Why it matters
This study adds human data measuring phthalate exposure in follicular fluid alongside urine, suggesting specific DEHP metabolites may be modestly associated with shorter cycle length and bleeding duration in subfertile women.
Limits
The study is restricted to women seeking fertility assistance, limiting generalizability. Menstrual parameters were self-reported via questionnaire rather than prospectively tracked. Exposure assessment was cross-sectional, and most examined endpoints and overall mixture analyses were null.
Cited by
- partial In women, higher phthalate exposure is associated with irregular menstrual cycles and an increased risk of endometriosis.