Associations between maternal plasma measurements of inflammatory markers and urinary levels of phenols and parabens during pregnancy: A repeated measures study.
BACKGROUND
Maternal immune system regulation is critical for maintenance of a healthy pregnancy and fetal development. Exposure to phenols and parabens is widespread, and may be linked to systemic inflammation and alteration of circulating immunological biomarkers.


OBJECTIVE
We sought to characterize associations between repeated measures of individual urinary phenols, parabens and plasma inflammatory markers across pregnancy.


METHODS
In the LIFECODES prospective birth cohort, we conducted a nested preterm birth case-control study, including 130 cases and 352 controls. In urine samples collected from each participant at up to four study visits during pregnancy, we measured concentrations of six phenols and four parabens, as well as five plasma inflammatory markers. We used multivariable linear mixed models to analyze repeated measures of exposures on inflammatory markers. We created and applied inverse probability weights to account for the sampling approach.


RESULTS
We observed bidirectional associations between select phenols and parabens and inflammatory markers. An interquartile range increase in triclosan (55.2 ng/mL) was associated with a 12.5% (95% CI: 3.67, 22.0) increase in C-reactive protein, a 7.95% (95% CI: 1.95, 14.3) increase in interleukin 10, and a 7.93% (95% CI: 3.82, 12,2) increase in tumor necrosis factor-α. Additionally, an interquartile range increase in 2,5-dichlorophenol (11.0 ng/mL) was associated with a 10% increase in C-reactive protein (95% CI: 1.92, 18.7). Conversely, an interquartile range increase in ethyl paraben (10.4 ng/mL) was associated with a 7.7% decrease in interleukin‑1β (95% CI: -14.1, -0.86).


CONCLUSIONS
Our findings can be organized into two thematic frameworks, one where concentrations of urinary phenols and parabens during pregnancy reflected a pro-inflammatory relationship with immunological biomarkers, and the other contrary theme - an anti-inflammatory relationship. These findings have implications for fetal development and reproductive outcomes, and emphasize the need for further research on immunological mechanisms of phenol and paraben action during pregnancy.
['Aung|Max T|MT|', 'Ferguson|Kelly K|KK|', 'Cantonwine|David E|DE|', 'Bakulski|Kelly M|KM|', 'Mukherjee|Bhramar|B|', 'Loch-Caruso|Rita|R|', 'McElrath|Thomas F|TF|', 'Meeker|John D|JD|']
D015415:Biomarkers D004784:Environmental Monitoring D004785:Environmental Pollutants D005260:Female D006801:Humans D008297:Male D018811:Maternal Exposure D010226:Parabens D010636:Phenols D011247:Pregnancy
Chlorinated phenols Cytokines Reproductive immunology