Does Older Age Modify Associations between Endocrine Disrupting Chemicals and Fecundability?

Area of Science:

• Environmental health
• Reproductive toxicology
• Endocrinology

Background:

• Urinary concentrations of endocrine-disrupting chemicals (EDCs), including phthalate metabolites, bisphenol A (BPA), and benzophenone (BP)-type UV filters, are linked to longer time-to-pregnancy (TTP).
• The role of couple's age in modifying these EDC-TTP associations remains unstudied.

Purpose of the Study:

• To investigate whether couple's age modifies the association between urinary EDC concentrations and time-to-pregnancy (TTP).
• To assess TTP in relation to specific phthalate metabolites, BPA, and BP-type UV filters, considering age as a potential effect modifier.

Main Methods:

• Prospective study defining TTP by menstrual cycles until pregnancy detection.
• Baseline urinary samples analyzed for phthalate metabolites, BPA, and BP-type UV filters.
• Fecundability odds ratios (FORs) calculated, adjusting for covariates and evaluating age-based effect modification (dichotomized at 35 years).

Main Results:

• No significant effect modification by partner's age was observed for any EDC.
• Suggestive evidence indicated longer TTP in females aged ≥35 years, with reduced fecundability for BP-2 (39%) and 4-hydroxybenzophenone (29%).
• No evidence of age-related modification was found for phthalate or BPA metabolite associations with TTP.

Conclusions:

• Couple's age does not appear to significantly modify the association between common urinary EDCs and time-to-pregnancy.
• Older maternal age (≥35 years) may be independently associated with longer TTP, particularly with exposure to certain UV filters.
• Further research is needed to fully elucidate the complex interplay between EDCs, age, and fecundability.