Periconception bisphenol and phthalate concentrations in women and men, time to pregnancy, and risk of miscarriage.
Level 3 - non-randomized controlled study
Prospective observational cohort study
PubMed 40311909 · doi:10.1016/j.envres.2025.121712
What was done
Researchers measured urinary concentrations of bisphenols and phthalates within the Generation R Next population-based cohort. Biomarkers were assessed preconception in 938 women actively attempting pregnancy, and in early pregnancy (mean gestational age 8.6 weeks) in 1,366 women and 1,202 men. Time to pregnancy, subfertility (conception delay >12 months or use of assisted reproductive technology), and miscarriage were tracked using questionnaires and ultrasound examinations.
What was found
The abstract reports statistical associations (all p < 0.05) without providing numerical point estimates or confidence intervals: - In women, higher preconception bisphenol S (BPS) and cyclohexane-1,2-dicarboxylic acid-monocarboxy isooctyl ester (mCOCH) were associated with longer time to pregnancy. - Higher female preconception concentrations of several phthalate metabolites (including mono-[(2-carboxymethyl)hexyl] phthalate, mEOHP, mCHpP, and mBzBP) were associated with shorter time to pregnancy, and higher mEHHP, mEOHP, and mBzBP were associated with lower odds of subfertility. - In men, higher early pregnancy concentrations of BPS and select phthalate metabolites were associated with shorter time to pregnancy or lower odds of subfertility. - Maternal preconception or early pregnancy BPS, phthalic acid, and mCHpP were associated with lower odds of miscarriage, whereas mono-carboxy-isoctyl phthalate, mCOCH, and cxmPHxP were associated with higher odds of miscarriage.
Why it matters
This study assesses how periconceptional exposures to plasticizers and replacement compounds relate to couple fecundity and pregnancy loss in a prospective cohort. The paradoxical and divergent associations across structurally related metabolites suggest complex exposure patterns that require replication.
Limits
The abstract reports no numerical effect sizes or confidence intervals. Testing multiple chemical compounds individually raises the likelihood of chance findings. Male urinary biomarkers were collected in early pregnancy rather than preconception. Spot urine measurements may inadequately capture long-term exposure to rapidly metabolized non-persistent chemicals.