Effects of maternal exposure to phthalates and bisphenol A during pregnancy on gestational age

Abstract

Objective Phthalates and bisphenol A (BPA) are ubiquitous environmental toxicants, present in high concentrations in numerous consumer products. We hypothesized that maternal exposure to phthalates and BPA in pregnancy is associated with shortened gestation. Methods Urinary phthalate and BPA metabolites from 72 pregnant women were measured at the last obstetric clinic visit prior to delivery. Using linear regression models, we estimated the change in gestational age associated with each interquartile range (IQR) increase in phthalate and BPA metabolite concentration. Results IQR increases in urinary mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and BPA concentrations were associated with 4.2 and 1.1 day decreases in gestation, respectively. When stratified by gender, these alterations were found only in male infants. Conclusions We conclude that MEHHP and BPA (free + glucuronide) are associated with reductions in gestation, with effects observed only in males. Our findings are consistent with the idea that these agents induce gender-specific alterations in signaling via PPAR-γ transcription factor, androgen precursors, and/or inflammatory mediators during the initiation of labor.

Maternal phthalate exposure during early pregnancy and at delivery in relation to gestational age and size at birth: A preliminary analysis

“…However, among females in the present study, ΣDBP levels earlier in pregnancy were associated with decreased birth weight. In contrast to previous studies (13,18-20,24), DEHP metabolites measured during the first trimester or at delivery were not associated with size or gestational age at birth. Our findings are also inconsistent with a case-control study performed in France which found no significant associations between prenatal phthalate metabolite levels and birth outcomes (16), however, this study was different from the current analysis in many aspects, including study population, design, and standardization of phthalate levels that could potentially explain this discrepancy.…”

“…Phthalate and BPA exposure among pregnant women have been associated with altered hormone levels (8,55,56), increased oxidative stress during pregnancy (49,57), and birth outcomes such as low birth weight (18,27) and decreased gestational age (20). However, entering concurrently measured phthalate metabolite and BPA levels into regression models together did not alter our results.…”

“…In addition, a meta-analysis of data from three birth cohorts found that maternal urinary mono-2-ethyl-5-hydroxyhexyl phthalate (MEHHP) concentrations in second and third trimesters were associated with lower birth weight, while mono-oxo-isononyl phthalate (MOiNP) was marginally associated with higher birth weight, after adjustment for other environmental exposures and covariates (18). Previous studies have also reported associations of in utero phthalate metabolites with decreased gestational age at birth (19,20) and increased risk of preterm birth (<37 weeks) (21-23); although, increased gestational age has also been reported in relation to maternal urinary monomethyl (MMP), monoethyl (MEP), and monobutyl (MBP) phthalates (15), and di-2-ethylhexyl phthalate (DEHP) metabolites (24). …”

Association of prenatal perchlorate, thiocyanate, and nitrate exposure with neonatal size and gestational age

“…We previously examined the relationship between cord blood concentrations of NIS inhibitors and newborn size among a sample of healthy mothers with full-term pregnancies [23]. In that study, we did not observe trends of decreasing newborn weight, length, or head circumference across increasing quartiles of cord blood perchlorate, thiocyanate, nitrate, or PEC.…”

“…The study population and protocol for this study have been described previously [23]. Briefly, we recruited 107 pregnant women (9–39 weeks gestation at enrollment) between December 2008 and July 2010 from the High-Risk Obstetric Clinic at Robert Wood Johnson University Hospital.…”