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Environmental inorganic arsenic (iAs) exposure is potentially related to abnormal blood pressure (BP) changes and abnormal platelet activation. However, limited epidemiological studies have explored the impacts of iAs exposure on platelet change mediated by BP, especially for pregnant women.Our purpose was to investigate the associations of arsenic exposure with blood pressure and platelet indices among pregnant women.The present study population included 765 pregnant women drawn from a prospective birth cohort study in Wuhan, China, recruited between October 2013 and April 2016. Urine sampled in the second trimester were used to assess arsenic species concentrations. The relative distribution of urinary arsenic species was used to measure human methylation capacity. BP parameters and platelet indices originated from the medical record. We applied multivariable linear regression models to explore the cross-sectional relationships between urinary arsenic metabolites, BP parameters, and platelet indices. We utilized mediation analysis to investigate the impacts of arsenic exposure on platelet indices through BP as mediator variables.We observed significant positive correlations between iAs and systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP). Pregnant women with higher methylation capacity to metabolize iAs characterized by higher secondary methylation index (SMI) and total methylation index (TMI) had a more significant reduction in SBP, DBP, and MAP. Pregnant women with higher DBP and MAP had higher platelet counts (PLC). A decreased PLC was found in subjects wither higher SMI. Additionally, SMI was negatively linked to PLC mediated through MAP.Obtained results suggested that higher methylation capacity to metabolize iAs might contribute to decreased PLC among pregnant women, and MAP might mediate the influence of SMI on PLC.

As endocrine disrupting chemicals, hexachlorocyclohexane (HCH) isomers were reported to impair the intrauterine growth. Although the findings of HCHs with preterm birth were well established, the associations with gestational age were limited. In the present study, we examined whether exposure to HCHs would influence gestational age. The study population included 1028 pregnant women and their offspring who were born in 2014–2015 from a birth cohort in Wuhan, China. Associations of the cord serum HCH levels with gestational age were estimated using generalized linear models. We found higher HCH levels in pregnant women, who were elder, had higher body mass index (BMI) before pregnancy, received higher education, or were exposed to smoking passively. For term birth, the 3rd tertiles of α-HCH and γ-HCH were significantly associated with shorter gestational age [crude β = −1.017, confidence interval (CI): − 2.017, − 0.018 for α-HCH, crude β = −1.068, CI: − 2.067, − 0.070 for γ-HCH], and relationships were similar after adjusted by covariates. Stratified analysis showed positive associations between α-HCH and gestational age for mothers younger than 25 years old (adjusted β = 0.610, CI: 0.061, 1.158), while showing negative relationships for mothers elder than 35 years old (adjusted β = −1.365, CI: −2.414, −0.317). In summary, our results indicated cord serum levels of HCHs were associated with gestational age at birth.

Prenatal life exposure to fine particulate matter (aerodynamic diameter less than or equal to 2.5 µm, PM2.5) has been linked with increased risk of adverse fetal development and birth outcomes in previous studies. However, to our knowledge, no study has investigated the association of maternal PM2.5 with the risk of fetal distress, which is a harmful fetal status and may lead to fetal brain damage, even fetal death. Therefore, we conducted a study to determine the association between maternal PM2.5 and fetal distress among 7835 mother-infant pairs from a birth cohort, in Wuhan, China, 2013–2015. The individual daily PM2.5 level was assessed using land use regression model. We evaluated the association of maternal PM2.5 level over the whole pregnancy with fetal distress by logistic regression model, and estimated the risk between PM2.5 exposure in specific trimester and fetal distress using generalized estimating equations. We observed that per 10 µg/m3 change of maternal PM2.5 level over the whole pregnancy was associated with 25% increased risk of fetal distress (95% confidence interval: 1.09–1.44). Further, we found PM2.5 level in the 2nd trimester, but not in the 1st and 3rd trimesters, was associated with fetal distress. Stratified analyses indicated that the association was only significant among infants who were born in cold seasons. Our study suggested that PM2.5 exposure during the whole pregnancy exhibited significant associations with the risk of fetal distress, and exposure in the 2nd trimester maybe the susceptible window. Further stratified analyses indicated that birth season is a possible modifier in the association.

Background Phthalates are endocrine disrupting chemicals (EDCs) that pose a serious hazard to the human health. Many epidemiological studies revealed a relationship between phthalates exposure and blood pressure in general population, while the relationship in pregnant women remains unknown. Objectives Aimed to elucidate whether phthalate exposure is associated with blood pressure among pregnant women. Methods This study included 636 participants from Wuhan, China. Urine samples were conducted repeatedly in three trimesters, and 9 phthalates were measured in these samples. After each urine was sampled, all the participants completed blood pressure measurements. Associations between repeated measurements of phthalate concentration and blood pressure were evaluated by using generalized estimating equations. Stratified analysis by fetus gender was conducted. Results Among the pregnant women with male fetuses, mono-i-butyl phthalate (MiBP) exposed in the 1st trimester was associated with the increased diastolic blood pressure (DBP) measured in the 2nd trimester, while the environmental risk score (ERS) measured in the 1st and 2nd trimester was positively associated with systolic blood pressure (SBP) and DBP in the 2nd trimester. No significant relationships were observed among all the population or pregnant women with female fetuses. Conclusions Exposure to higher levels of MiBP may be related to increased blood pressure during pregnancy in pregnant women with male fetuses.