Preterm birth in relation to the bisphenol A replacement, bisphenol S, and other phenols and parabens

Abstract

Introduction: Preterm birth continues to be a significant public heath concern and is a leading cause of perinatal and infant mortality. Environmental exposures to phenols and parabens are suspected to potentially contribute to the pathology of preterm birth, yet limited human studies have characterized the extent to which these toxicants are associated with birth outcomes. Methods:We examined the associations between phenols, parabens, and preterm birth, within pregnant women who were recruited early in gestation into the LIFECODES cohort at Brigham and Women's Hospital in Boston, Massachusetts. Urine samples were collected at up to 4 time points in pregnancy and analyzed for phenols and parabens. We selected 130 cases of preterm birth (defined as delivery before 37 weeks gestation), and 350 random controls. We categorized preterm birth subtypes based on clinical presentation and identified 75 cases of spontaneous preterm birth (characterized by spontaneous preterm labor and/or preterm premature rupture of membranes), and 37 cases of placental preterm birth (characterized by preeclampsia and/or intrauterine growth restriction). We used multivariate logistic regression with visit specific and geometric averages of phenols and parabens to determine associations with preterm birth. Results:We observed moderate variability in urinary phenol and paraben concentrations over pregnancy with intraclass correlation coefficients ranging between 0.45 -0.68. Regression analyses indicated mostly null associations. We observed inverse associations, notably between 2,5-dichlorophenol and overall preterm birth (adjusted odds ratio [95% confidence interval, CI]: 0.79 [0.67 -0.94]), and this relationship was consistent by study visit. Conversely, ethyl paraben was associated with increased risk for placental preterm birth (adjusted odds ratio [95% CI]: 1.47

Application of an analytical framework for multivariate mediation analysis of environmental data

“…When focusing on spontaneous preterm birth, four toxicants (2,4-DCP, 2,5-dichlorophenol [2,5-DCP], triclosan [TCS], and 1-PHE) were associated with decreased odds (Supplementary Data 1B). Similar directions of associations were observed in a previous analysis of these phenols in the larger LIFECODES cohort as well 25 . Modeling gestational age at delivery revealed three phthalate metabolites (MEHHP, MEOHP, and MECPP) associated with decreased gestational age at delivery (Fig.…”

Application of a novel analytical pipeline for high-dimensional multivariate mediation analysis of environmental data

“…When focusing on spontaneous preterm birth, five toxicants (2,4-DCP, 2,5-dichlorophenol [2,, triclosan [TCS], 9hydroxyphenanthrene [9-PHE], and 1-PHE) were associated with decreased odds (Supplemental Figure 2). Similar directions of associations were observed in a previous analysis of these phenols in the larger LIFECODES cohort as well 25 . Expectedly, modeling gestational age at delivery revealed that the same phthalate metabolites (MEHP, MEHHP, MEOHP, and MECPP) that were suggestively associated with preterm birth were also suggestively associated with decreased gestational age at delivery (Figure 2).…”

Determination of prenatal exposure to parabens and triclosan and estimation of maternal and fetal burden

“…One of the most debatable issues of PBs and TCS exposure is the risk that may arise for both the mother and the infant. There are animal studies that claim preterm birth or miscarriage after animals’ exposure to PBs and/or TCS [ 46 , 47 ]. Although, this refers to animals, which means to a little different organisms, this fact raises concerns about human pregnancies and the effects that exposure to these substances would cause.…”

“…It has already been proved that both TCS and PBs are inversely associated with thyroid hormones (T3, T4, TSH) [ [48] , [49] , [50] ], a fact that is a little bit concerning considering that these hormones define also infant’s hormones system. Except for the aforementioned, PBs are also negatively associated with maternal blood pressure [ 51 ] and EtPB has been strongly associated with preterm birth [ 47 ]. TCS is associated with maternal blood pressure [ 52 ].…”