RESUMO
BACKGROUND: Preterm birth is a global public health issue and rates in Puerto Rico are consistently among the highest in the USA. Exposures to environmental contaminants might be a contributing factor. METHODS: In a preliminary analysis from the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) cohort (nâ¯=â¯1090), we investigated the association between urinary phthalate metabolite concentrations measured at three study visits (targeted at 20, 24, and 28â¯weeks of gestation) individually and averaged over pregnancy with gestational age at delivery and preterm birth. We additionally assessed differences in associations by study visit and among preterm births with a spontaneous delivery. RESULTS: Compared to women in the general USA population, urinary concentrations of metabolites of di-n-butyl phthalate (DBP) and di-isobutyl phthalate (DiBP) were higher among pregnant women in Puerto Rico. Interquartile range (IQR) increases in pregnancy-averages of urinary metabolites of DBP and DiBP were associated with shorter duration of gestation and increased odds of preterm birth. An IQR increase in mono-n-butyl phthalate (MBP), a metabolite of DBP, was associated with 1.55â¯days shorter gestation (95% confidence interval [CI]â¯=â¯-2.68, -0.42) and an odds ratio (OR) of 1.42 (95% confidence interval [CI]: 1.07, 1.88) for preterm birth. An IQR increase in mono-isobutyl phthalate (MiBP), a metabolite of DiBP, was associated with 1.16â¯days shorter gestation (95% CIâ¯=â¯-2.25, -0.08) and an OR of 1.32 (95% CI: 1.02, 1.71) for preterm birth. Associations were greatest in magnitude for urinary concentrations measured at the second study visit (median 23â¯weeks gestation). DiBP metabolite associations were greatest in magnitude in models of spontaneous preterm birth. No associations were detected with other phthalate metabolites, including those of di-2-ethylhexyl phthalate. CONCLUSION: Among pregnant women in the PROTECT cohort, DBP and DiBP metabolites were associated with increased odds of preterm birth. These exposures may be contributing to elevated rates of preterm birth observed in Puerto Rico.
Assuntos
Poluentes Ambientais/urina , Ácidos Ftálicos/urina , Plastificantes/análise , Gravidez/urina , Nascimento Prematuro/epidemiologia , Adolescente , Adulto , Monitoramento Biológico , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Razão de Chances , Nascimento Prematuro/urina , Porto Rico/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Presence of Bisphenol A (BPA) has been documented worldwide in a variety of human biological samples. There is growing evidence that low level BPA exposure may impact placental tissue development and thyroid function in humans. The aim of this present pilot study was to determine urinary concentrations of BPA during the last trimester of pregnancy among a small subset of women in Mexico City, Mexico and relate these concentrations to risk of delivering prematurely. METHODS: A nested case-control subset of 60 participants in the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) study in Mexico City, Mexico were selected based on delivering less than or equal to 37 weeks of gestation and greater than 37 weeks of gestation. Third trimester archived spot urine samples were analyzed by online solid phase extraction coupled with high performance liquid chromatography isotope dilution tandem mass spectrometry. RESULTS: BPA was detected in 80.0% (N = 48) of the urine samples; total concentrations ranged from < 0.4 µg/L to 6.7 µg/L; uncorrected geometric mean was 1.52 µg/L. The adjusted odds ratio of delivering less than or equal to 37 weeks in relation to specific gravity adjusted third trimester BPA concentration was 1.91 (95%CI 0.93, 3.91, p-value = 0.08). When cases were further restricted to births occurring prior to the 37th week (n = 12), the odds ratio for specific-gravity adjusted BPA was larger and statistically significant (p < 0.05). CONCLUSIONS: This is the first study to document measurable levels of BPA in the urine of a population of Mexican women. This study also provides preliminary evidence, based on a single spot urine sample collected during the third trimester, that pregnant women who delivered less than or equal to 37 weeks of gestation and prematurely (< 37 weeks) had higher urinary concentrations of BPA compared to women delivering after 37 weeks.
Assuntos
Exposição Ambiental/efeitos adversos , Poluentes Ambientais/intoxicação , Fenóis/intoxicação , Nascimento Prematuro/induzido quimicamente , Adulto , Compostos Benzidrílicos , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , México/epidemiologia , Fenóis/urina , Projetos Piloto , Gravidez , Terceiro Trimestre da Gravidez/efeitos dos fármacos , Terceiro Trimestre da Gravidez/urina , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/urinaRESUMO
BACKGROUND: Rates of preterm birth have been rising over the past several decades. Factors contributing to this trend remain largely unclear, and exposure to environmental contaminants may play a role. OBJECTIVE: We investigated the relationship between phthalate exposure and preterm birth. METHODS: Within a large Mexican birth cohort study, we compared third-trimester urinary phthalate metabolite concentrations in 30 women who delivered preterm (< 37 weeks of gestation) with those of 30 controls (> or = 37 weeks of gestation). RESULTS: Concentrations of most of the metabolites were similar to those reported among U.S. females, although in the present study mono-n-butyl phthalate (MBP) concentrations were higher and monobenzyl phthalate (MBzP) concentrations lower. In a crude comparison before correcting for urinary dilution, geometric mean urinary concentrations were higher for the phthalate metabolites MBP, MBzP, mono(3-carboxylpropyl) phthalate, and four metabolites of di(2-ethyl-hexyl) phthalate among women who subsequently delivered preterm. These differences remained, but were somewhat lessened, after correction by specific gravity or creatinine. In multivariate logistic regression analysis adjusted for potential confounders, elevated odds of having phthalate metabolite concentrations above the median level were found. CONCLUSIONS: We found that phthalate exposure is prevalent among this group of pregnant women in Mexico and that some phthalates may be associated with preterm birth.
Assuntos
Exposição Ambiental , Exposição Materna , Ácidos Ftálicos/urina , Nascimento Prematuro/urina , Adulto , Estudos de Casos e Controles , Feminino , Humanos , México , Gravidez , Terceiro Trimestre da Gravidez , Fatores de Risco , Adulto JovemRESUMO
OBJECTIVE: To evaluate associations between maternal serum uric acid (UA) levels, maternal status, and fetal outcome. METHODS: Maternal UA, urinary protein-creatinine ratio (P/C), blood pressure (BP), gestational age at delivery, and birth weight were evaluated in hypertensive pregnant women (n = 58). These were divided into two groups: high UA (> or =357 micromol/L) or normal UA (<357 micromol/L). RESULTS: Maternal diastolic BP and P/C ratio were higher in pregnant women with elevated UA levels. Systolic BP, gestational age and birth weight were not significantly different. CONCLUSION: UA equal or above 357 micromol/L in pregnant hypertensive women was associated with proteinuria and diastolic BP, but not with fetal outcome.