Gender associations between phthalate exposure and biomarkers of oxidative stress: A prospective cohort study.

Previous epidemiologic research has shown that phthalate exposure in pregnant women is related to adverse birth outcomes in a sex-specific manner. However, the biological mechanism of phthalate exposure that causes these birth outcomes remains poorly defined. In this research, we investigated the association between phthalate exposure and placental oxidative stress in a large population-based cohort study, aiming to initially explore the relationship between phthalate exposure and gene expression in placental oxidative stress in a sex-specific manner. Quantitative PCR was performed to measure the expression of placental inflammatory mRNAs (HO-1, HIF1α, and GRP78) in 2469 placentae. The multiple linear regression models were used to investigate the associations between mRNA and urinary phthalate monoesters. Phthalate metabolites monomethyl phthalate (MMP) and mono-n-butyl phthalate (MBP) were positively correlated with higher HIF1α expression in placentae of male fetuses (p < .05). Mono-benzyl phthalate (MBzP) increased the expression of HO-1, HIF1α, and GRP78 in placentae of male fetuses, and mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) up-regulated the expression of HIF1α and GRP78. Additionally, mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) was negatively correlated with HO-1, HIF1α, and GRP78 in placentae of female fetuses. Maternal phthalate exposure was associated with oxidative stress variations in placental tissues. The associations were closer in the placentas of male fetuses than in that of female ones. The placenta oxidative stress is worth further investigation as a potential mediator of maternal exposure-induced disease risk in children.

The effect of phthalates exposure during pregnancy on asthma in infants aged 0 to 36 months: a birth cohort study.

This cohort study sought to investigate the effects of phthalates exposure during pregnancy on offspring asthma and its association with placental stress and inflammatory factor mRNA expression levels. A total of 3474 pregnant women from the China Ma'anshan birth cohort participated in this study. Seven phthalate metabolites were detected in urine samples during pregnancy by solid phase extraction-high-performance liquid chromatography tandem mass spectrometry. Placenta stress and inflammation mRNA expression were assessed by real-time quantitative polymerase chain reaction (RT-qPCR). Early pregnancy may be the critical period when phthalates exposure increases the risk of asthma in infants and young children, and there is a certain gender difference in the risk of asthma in infants and young children. Moreover, through the placenta stress and inflammatory factor associated with infant asthma found anti-inflammatory factor of interleukin-10 (IL-10) mRNA expression will reduce the risk of 36-month-old male infant asthma. The expression of interleukin-4(IL-4) and macrophage (M2) biomarker cluster of differentiation 206(CD206) mRNA reduced the risk of asthma in 18-month-old female infants. Placental stress and inflammatory response were analyzed using mediating effects. Tumor necrosis factor-α (TNFα) showed a complete mediating effect between mono-benzyl phthalate (MBzP) exposure in early pregnancy and asthma in 12-month-old males, and IL-10 also showed a complete mediating effect between mono-n-butyl phthalate (MBP) exposure in early and late pregnancy and asthma in 36-month-old males. In summary, exposure to phthalates during pregnancy may contribute to the development of asthma in infants, which may be associated with placental stress and inflammation.

Association of serum bisphenol AF concentration with depressive symptoms in adolescents: A nested case-control study in China.

BACKGROUND: As an important alternative to bisphenol A (BPA), bisphenol AF (BPAF) is widely used and can be detected in multiple human biological samples. However, there are few studies on neurotoxicity of BPAF at present. In particular, no epidemiological studies have investigated BPAF in relation to depressive symptoms in adolescents. Here, our study aimed to evaluate the associations between serum BPAF concentrations and depressive symptoms in adolescents. METHODS: A nested case-control study within an ongoing longitudinal prospective adolescent cohort that was established in Huaibei, China was conducted. A total of 175 participants who had new-onset depressive symptoms (cases) and 175 participants without depressive symptoms (controls) were included. Serum BPAF concentrations was measured using ultra-high-performance liquid chromatography-tandem mass spectrometry. The associations between BPAF exposure and the risk of depressive symptoms in adolescents were assessed using conditional logistic regression. The dose-response relationship between BPAF level and depressive symptoms was estimated using restricted cubic spline analyses. RESULTS: In this study, the detection rate of serum BPAF was 100%, and the median (interquartile range, IQR) serum BPAF concentration was 5.24 (4.41-6.11) pg/mL in the case group and 4.86 (4.02-5.77) pg/mL in the control group (P = 0.009). Serum BPAF exposure was a risk factor for depressive symptoms (odds ratio (OR)= 1.132, 95% confidence interval (CI):1.013-1.264). After adjustment for all for confounders, compared with the low-exposure group, the high-exposure group had a 2.806-fold increased risk of depressive symptoms (OR=2.806, 95% CI: 1.188-6.626). Stratified analysis by sex revealed that males were more vulnerable to BPAF exposure than females. After adjustment for all confounders, compared with the low-exposure group, the relative risk of depressive symptoms in the high-exposure group was 3.858 (95% CI: 1.118-12.535) for males, however, no significant association between BPAF exposure and depressive symptoms was found in females. In addition, there was a marked linear association between BPAF exposure and the risk of depressive symptoms in the total population and in males. CONCLUSIONS: The adolescents in this study were widely exposed to low levels of BPAF. A significant positive association was found between serum BPAF levels and the risk of depressive symptoms. The association was significantly modified by sex, and males were more vulnerable to BPAF exposure than females.

Acute associations between air pollution on premature rupture of membranes in Hefei, China.

Numerous studies had focused on the association between air pollution and health outcomes in recent years. However, little evidence is available on associations between air pollutants and premature rupture of membranes (PROM). Therefore, we performed time-series analysis to evaluate the association between PROM and air pollution. The daily average concentrations of PM2.5, SO2 and NO2 were 54.58 µg/m3, 13.06 µg/m3 and 46.09 µg/m3, respectively, and daily maximum 8-h average O3 concentration was 95.67 µg/m3. The strongest effects of SO2, NO2 and O3 were found in lag4, lag06 and lag09, and an increase of 10 µg/m3 in SO2, NO2 and O3 was corresponding to increase in incidence of PROM of 8.74% (95% CI 2.12-15.79%), 3.09% (95% CI 0.64-5.59%) and 1.68% (95% CI 0.28-3.09%), respectively. There were no significant effects of PM2.5 on PROM. Season-specific analyses found that the effects of PM2.5, SO2 and O3 on PROM were more obvious in cold season, but the statistically significant effect of NO2 was observed in warm season. We also found the modifying effects by maternal age on PROM, and we found that the effects of SO2 and NO2 on PROM were higher among younger mothers (< 35 years) than advanced age mothers (≥ 35 years); however, ≥ 35 years group were more vulnerable to O3 than < 35 years group. This study indicates that air pollution exposure is an important risk factor for PROM and we wish this study could provide evidence to local government to take rigid approaches to control emissions of air pollutants.

Aluminum and magnesium status during pregnancy and placenta oxidative stress and inflammatory mRNA expression: China Ma'anshan birth cohort study.

The aim of this study was to explore the impact of prenatal Al and Mg on placental oxidative stress and inflammatory mRNA expression. A total of 2519 pregnant women from the China Ma'anshan birth cohort participated in this study. Al and Mg levels were measured by inductively coupled plasma mass spectrometry (ICP-MS). Placental stress and inflammatory mRNA expression were assessed by RT-PCR. The median Al levels in the first and second trimesters of pregnancy and in cord blood were higher than the corresponding median Mg levels. Predictors of lower Al and Mg levels included Han ethnicity and high education according to a mixed linear model. Multiple linear regression analysis revealed that Al and Al/Mg levels had a positive association with inflammatory mRNA expression and placental oxidative stress in the second trimester of pregnancy. A negative association existed between Al and Al/Mg levels and inflammatory mRNA expression and placenta oxidative stress in the cord blood, with the exception of IL-1ß expression. In conclusion, prenatal Al and Mg status was associated with placental oxidative stress and inflammatory mRNA expression. More preclinical studies are needed to confirm the relevant mechanism.

Prenatal phthalate exposure in relation to gestational age and preterm birth in a prospective cohort study.

This study enrolled 3266 pregnant women, to explore the relationship of prenatal phthalate exposure with the risk of preterm birth and gestational age. All participants filled questionnaires and provided with up to three urine samples during three trimesters. Seven phthalate metabolites in urines were measured. The incidences of very preterm, late preterm, early-term, late-term and postterm births were 0.58%, 3.52%, 24.22%, 10.53%, and 0.34%, respectively. Non-linear relationships were shown between phthalate metabolites and gestational age. Except for monomethyl phthalate (OR = 1.65, 95%CI = 1.17-2.34), the average concentrations of phthalate metabolites were associated with a slightly and insignificantly increased risk of overall preterm birth (<37+0 gestational weeks). Through a restricted cubic spline regression, phthalate metabolites were found to be related to the risk of overall preterm birth in a linear manner (p-value >0.05) or a non-linear manner (p-value <0.05). All curves indicated the overall preterm birth risk rose with the increase of phthalate metabolite concentrations. Finally, compared with full-term birth (39+0 to 40+6 gestational weeks), phthalate metabolites were associated with the elevated risks of very preterm, late preterm and postterm births, although some relationships were not statistically significant. In conclusion, these findings suggested non-linear associations between phthalate metabolites and gestational age. Exposure to some phthalate metabolites was associated with increased risks of overall preterm birth and postterm birth.

Thyroid autoantibodies in pregnancy are associated with hypertensive disorders of pregnancy: Ma'anshan Birth Cohort Study.

OBJECTIVE: Hypertensive disorders of pregnancy (HDP) have been associated with adverse health outcomes for both mothers and children. Previous studies examining associations of maternal thyroid autoantibodies with HDP indicate conflicting results. The objective of this study was to examine associations of maternal thyroid autoantibody positivity in the first and the second trimesters with the risk of HDP. DESIGN, PARTICIPANTS AND MEASUREMENTS: In the Ma'anshan Birth Cohort study, a population-based prospective study in China, a total of 3474 pregnant women were enrolled between May 2013 and September 2014. Thyroid autoantibodies, including antithyroperoxidase autoantibody (TPOAb) and antithyroglobulin autoantibody (TgAb), as well as thyroid function tests, were measured in both the first and the second trimesters in 2893 pregnant women. Multivariate logistic regression analyses were conducted to calculate the odds ratio (OR) and 95% confidence interval (CI) for the associations between thyroid autoantibodies and HDP. RESULTS: Multivariate logistic regression analyses showed that TPOAb positivity in the first trimester was associated with a 1.80 (95% CI = 1.17-2.78) increased odds of HDP after adjustment for confounders, which was mainly due to an increased risk of gestational hypertension (OR = 1.93, 95% CI = 1.17-3.18). In addition, TgAb positivity in the first trimester was associated with a higher risk of HDP (OR = 1.78, 95% CI = 1.16-2.73) after adjustment for confounders, which was mainly due to an increased risk of gestational hypertension (OR = 1.89, 95% CI = 1.15-3.11). These associations were also seen among euthyroid women. Women with positive TPOAb in the second trimester seemed to have a higher risk of gestational hypertension (OR = 1.87, 95% CI = 1.02-3.43) after adjustment for confounders. However, among euthyroid women, TPOAb positivity in the second trimester was not associated with HDP. The TgAb status in the second trimester was not associated with HDP. CONCLUSIONS: Our results show that TPOAb positivity and TgAb positivity in the first trimester are associated with an increased risk of HDP. These data demonstrate that these associations are even seen among euthyroid women.

Maternal serum arsenic level during pregnancy is positively associated with adverse pregnant outcomes in a Chinese population.

Arsenic is an environmental toxicant. The association of gestational arsenic exposure with adverse pregnant outcomes remains controversial. This study was to investigate the association of serum As level with adverse pregnant outcomes in a large Chinese cohort population. Total 3194 mother-and-infant pairs were recruited from the China-Anhui Birth Cohort Study. Maternal serum arsenic (As) concentration was measured using hydride generation-atomic fluorescence spectrometry. Subjects were divided into L-As group and H-As group in accordance to the 75th percentile of serum As concentration. The associations of serum As level during gestation with adverse pregnant outcomes were analyzed. The incidence of small-for-gestational-age (SGA) newborns was elevated in H-As group compared to L-As group (9.9% vs 7.6%, P = .044). After controlling confounders and stratified analysis, the adjusted OR for SGA was significant only in girls with H-As but not in boys. Moreover, the incidence of preterm delivery (PTD) was elevated in H-As group compared to L-As group (7.0% vs 4.8%, P = .016). Further analysis found that the adjusted OR for moderate-to-late PTD was 1.47 (95%CI: 1.03, 2.09; P = .034) in H-As group as compared with L-As group. These results indicate that maternal serum As level during gestation is positively associated with adverse pregnant outcomes.

Prenatal phthalate exposure and placental size and shape at birth: A birth cohort study.

OBJECTIVE: There is concern over the potential placental effects of prenatal phthalate exposure, and the potential adverse effects of prenatal phthalate exposure require further study; however, few data are available in humans. We investigated the associations between phthalate exposure in each trimester and both placental size and shape at birth. METHODS: We measured the urinary concentrations of phthalate metabolites among 2725 pregnant women in the Ma'anshan Birth Cohort. Before collecting urine samples from each of the three trimesters, the pregnant women were interviewed via questionnaires. Placental information was obtained from hospital records. We estimated the sex-specific associations between urinary phthalate concentrations in each trimester and both placental size and shape at birth using adjusted multiple regression. A linear mixed model was used for the repeated measures analysis with subject-specific random intercepts and slopes for gestational age at sample collection to test the effect of phthalate levels on placental size and shape and to estimate the effect sizes. RESULTS: Overall, placental breadth increased by 0.148cm (95% CI: 0.078, 0.218) with each 1 ln-concentration increase in MBP in the first trimester. The difference between placental length and breadth (length-breadth) decreased by 0.086cm (95% CI: -0.159, -0.012) and 0.149cm (95% CI: -0.221, -0.076) with each 1 ln-concentration increase in MMP and MBP, respectively, in the first trimester. In the second trimester, placental thickness increased by 0.017cm (95% CI: 0.006, 0.027), 0.020cm (95% CI: 0.004, 0.036), 0.028cm (95% CI: 0.007, 0.048), and 0.035cm (95% CI: 0.018, 0.053) with each 1 ln-concentration increase in MMP, MBP, MEOHP, and MEHHP, respectively. In the third trimester, placental thickness increased by 0.037cm (95% CI: 0.019, 0.056) and 0.019cm (95% CI: 0, 0.037) with each 1 ln-concentration increase in MBP and MEHP, respectively. Multiple linear regression for each offspring sex indicated that prenatal phthalate exposure increased placental thickness in both the first and second trimesters in males, whereas the corresponding relationship was close to null in females. Linear mixed models (LMMs) yielded similar results. CONCLUSION: Our results suggest the presence of associations between prenatal phthalate exposure and placental size and shape. Exposure to certain phthalates may cause the placenta to become thicker and more circular. Associations appeared stronger for the subsample representing male offspring than those for the subsample representing female offspring. Given the few studies on this topic, additional research is warranted.

High serum lead concentration in the first trimester is associated with an elevated risk of small-for-gestational-age infants.

A recent study found that gestational serum Pb concentration is associated with an increased risk of preterm birth. The purpose of this study was to analyze whether gestational Pb exposure elevates risk of small-for-gestational-age (SGA) births in a Chinese population. In the present study, total 3125 mother-infant pairs were recruited from the China-Anhui Birth Cohort Study (C-ABCS). Pb concentration in maternal serum was detected by GFAAS. All subjects were classified into three groups according to the tertile division of serum Pb concentration: L-Pb (low-Pb, <1.18µg/dl), M-Pb (medium-Pb, 1.18-1.70µg/dl), and H-Pb (high-Pb, ≥1.71µg/dl). There was no difference on birth length, head circumference and chest circumference among different groups. The rate of SGA was 6.2% in subjects with L-Pb, 8.7% in subjects with M-Pb, and 10.1% in subjects with H-Pb, respectively. The adjusted OR of SGA was 1.45 (95%CI: 1.04, 2.02; P=0.03) in subjects with M-Pb and 1.69 (95%CI: 1.22, 2.34; P=0.002) in subjects with H-Pb. Interestingly, the rate of SGA infants was elevated only in subjects with H-Pb in the first trimester (adjusted OR: 2.13; 95%CI: 1.24, 3.38; P=0.007). Collectively, high serum Pb level in the first trimester is associated with an elevated risk of SGA infants.

Maternal Serum Zinc Concentration during Pregnancy Is Inversely Associated with Risk of Preterm Birth in a Chinese Population.

BACKGROUND: Evidence exists that maternal zinc status during pregnancy is linked to adverse pregnancy outcomes including abortion, fetal growth restriction, and neural tube defects. However, it remains unclear whether maternal serum zinc concentration (SZC) during pregnancy is associated with risk of preterm birth. OBJECTIVE: This study was designed to investigate the association between maternal SZC during pregnancy and risk of preterm birth. METHODS: For this substudy of the China-Anhui Birth Cohort Study, 3081 maternal-singleton pairs with detailed birth records and available serum samples were identified. The maternal SZC was determined with flame atomic absorption spectroscopy. A total of 169 preterm births were identified. In this study, the women were divided into tertiles on the basis of their SZC: low (<76.7 µg/dL), medium (76.7-99.6 µg/dL), and high (≥99.7 µg/dL). The ORs for preterm birth were estimated by using multiple logistic regression models. RESULTS: The median SZC was 87.3 µg/dL (range: 11.1-211 µg/dL). Incidences of preterm birth were 7.3% and 6.0% among subjects with low and medium SZCs, respectively, which were significantly higher than 3.1% among subjects with a high SZC [ORs (95% CIs) for low and medium SZCs: 2.45 (1.60, 3.74), P < 0.001, and 2.00 (1.29, 3.09), P < 0.01, respectively]. After adjustment for prepregnancy body mass index, maternal age, time of serum collection, gravidity, parity, and monthly income, adjusted ORs were 2.41 (95% CI: 1.57, 3.70; P < 0.001) and 1.97 (95% CI: 1.27, 3.05; P < 0.01) among subjects with low and medium maternal SZCs. CONCLUSIONS: Maternal serum zinc concentration during pregnancy is inversely associated with risk of preterm birth in the Chinese population, and the results are driven by maternal SZC in the first trimester.

Cord blood vitamin D and neurocognitive development are nonlinearly related in toddlers.

BACKGROUND: Little is known about the relation between vitamin D status in early life and neurodevelopment outcomes. OBJECTIVE: This study was designed to examine the association of cord blood 25-hydroxyvitamin D [25(OH)D] at birth with neurocognitive development in toddlers. METHODS: As part of the China-Anhui Birth Cohort Study, 363 mother-infant pairs with complete data were selected. Concentrations of 25(OH)D in cord blood were measured by radioimmunoassay. Mental development index (MDI) and psychomotor development index (PDI) in toddlers were assessed at age 16-18 mo by using the Bayley Scales of Infant Development. The data on maternal sociodemographic characteristics and other confounding factors were also prospectively collected. RESULTS: Toddlers in the lowest quintile of cord blood 25(OH)D exhibited a deficit of 7.60 (95% CI: -12.4, -2.82; P = 0.002) and 8.04 (95% CI: -12.9, -3.11; P = 0.001) points in the MDI and PDI scores, respectively, compared with the reference category. Unexpectedly, toddlers in the highest quintile of cord blood 25(OH)D also had a significant deficit of 12.3 (95% CI: -17.9, -6.67; P < 0.001) points in PDI scores compared with the reference category. CONCLUSIONS: This prospective study suggested that there was an inverted-U-shaped relation between neonatal vitamin D status and neurocognitive development in toddlers. Additional studies on the optimal 25(OH)D concentrations in early life are needed.

Sex-specific and time-dependent effects of prenatal stress on the early behavioral symptoms of ADHD: a longitudinal study in China.

There is increasing evidence that prenatal stressful life events (SLEs) may be a potential risk factor for attention-deficit hyperactivity disorder (ADHD), but the sex-specific and time-dependent effects of prenatal stress on ADHD are less clear. In this prospective longitudinal study, data on prenatal SLEs during different stages of gestation and indicators of buffers against stress, including maternal social support and avoidance coping, were obtained from 1765 pregnant women at 32 weeks of gestation. The behavioral symptoms of ADHD in children aged 48-54 months were evaluated by reports from the parents. There were 226 children (12.8%) above the clinically significant cutoff for ADHD. After adjusting for potential confounders, boys whose mother experienced severe SLEs in the second trimester had a significantly increased risk (OR = 2.41, 95% CI: 1.03-5.66) of developing ADHD symptoms compared with boys whose mothers did not experience severe SLEs at this time. However, no significantly increased risk of ADHD symptoms was observed in girls born to mothers experienced prenatal severe SLEs. Additionally, significant interaction effects of prenatal SLEs, social support and coping style on ADHD symptoms were found in males. Boys whose mothers experienced severe SLEs during the second trimester accompanied by a higher score for avoidance coping (OR = 3.31, 95% CI: 1.13-9.70) or a lower score for social support (OR = 4.39, 95% CI: 1.05-18.31) were likely to be at a higher risk for ADHD symptoms. The epidemiological evidence in this prospective follow-up study suggests that the effect of prenatal SLEs on ADHD symptoms in offspring may depend on the timing of prenatal stress and may vary according to the sex of the offspring.

Does prenatal maternal stress impair cognitive development and alter temperament characteristics in toddlers with healthy birth outcomes?

AIM: The aim of this study was to assess the cognitive and behavioural development of children with healthy birth outcomes whose mothers were exposed to prenatal stress but did not experience pregnancy complications. METHOD: In this prospective study, self-reported data, including the Prenatal Life Events Checklist about stressful life events (SLEs) during different stages of pregnancy, were collected at 32 to 34 weeks' gestation. Thirty-eight healthy females (mean age 27 y 8 mo, SD 2 y 4 mo) who were exposed to severe SLEs in the first trimester were defined as the exposed infant group, and 114 matched comparison participants were defined as the unexposed infant group (1:3). Maternal postnatal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale. The Bayley Scales of Infant Development and the Toddler Temperament Scale were used to evaluate the cognitive development and temperament characteristics of the infants with healthy birth outcomes when they were 16 to 18 months old. RESULTS: A randomized block multivariate analysis of covariance showed that the mental development index scores of the infants of mothers with prenatal exposure to SLEs in the first trimester averaged seven points (95% confidence interval 3.23-10.73 points) lower than those of the unexposed infants. Moreover, the infants in the exposed group achieved higher scores for regularity (adjusted mean [SD] 2.77 [0.65] vs. 2.52 [0.78], F(5,146) =5.27, p=0.023) and for persistence and attention span (adjusted mean 3.61 [0.72] vs. 3.35 [0.52], F(5,146) =5.51, p=0.020). INTERPRETATION: This study provides evidence that lower cognitive ability and less optimal worse behavioural response in infants might independently result from prenatal maternal stress.

A systematic review and quantitative assessment of sleep-disordered breathing during pregnancy and perinatal outcomes.

PURPOSE: Previous investigations have suggested a strong association between sleep-disordered breathing (SDB) during pregnancy and perinatal outcomes. However, the results of the following replication studies were not always concordant. Therefore, this meta-analysis was conducted to evaluate the more reliable estimate. METHODS: A systematic literature search was performed on PubMed, Springer Link, and EMBASE to identify all eligible studies published before August 2013. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using fixed or random effects model. RESULTS: A total of 24 publications met the inclusion criteria and were included in this meta-analysis. Findings demonstrated that moderate-to-severe SDB during pregnancy was associated with gestational diabetes mellitus (OR=1.78; 95% CI, 1.29 to 2.46), pregnancy-related hypertension (OR=2.38; 95% CI, 1.63 to 3.47), preeclampsia (OR=2.19; 95% CI, 1.71 to 2.80), preterm delivery (OR=1.98; 95% CI, 1.59 to 2.48), low birth weight (OR=1.75; 95% CI, 1.33 to 2.32), neonatal intensive care unit (NICU) admission (OR=2.43; 95% CI, 1.61 to 3.68), intrauterine growth restriction (OR=1.44; 95% CI, 1.22 to 1.71), and Apgar score of <7 at 1 min (OR=1.78; 95% CI, 1.10 to 2.91) based on all studies but not gestational age and birth weight. CONCLUSIONS: This meta-analysis revealed that moderate-to-severe SDB during pregnancy may be associated with most of adverse perinatal outcomes. Further well-designed studies are warranted to confirm our findings.

The role of preexisting diabetes mellitus on incidence and mortality of endometrial cancer: a meta-analysis of prospective cohort studies.

OBJECTIVE: The results of cohort studies are controversial regarding the association between preexisting diabetes mellitus (DM) and the risk of endometrial cancer (EC) incidence and mortality. The aim of this meta-analysis was to assess whether an association exists between them in prospective studies. METHODS: The PubMed and EMBASE database were searched for prospective cohort studies of preexisting DM on EC occurrence, mortality outcomes, updated up to June 2012. Data were independently extracted by 2 investigators using a standardized protocol. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were estimated by the use of fixed-effect or random-effect models. Between-study heterogeneity was investigated using χ(2)-based Cochran Q statistic test and I statistics. RESULTS: A total of 21 cohort studies (20 articles) involving 12,195 incident cases and 575 deaths caused by EC were included in the analysis. Among these, 15 studies reported the risk of EC incidence, and 6 studies reported risk of EC mortality. The meta-analysis showed that DM was associated with an increased incidence of EC (SRR, 1.81; 95% CI, 1.38-2.37; test for heterogeneity: Q = 280.96, P < 0.001, I(2) = 95.4%), compared with individuals without diabetes or the general population. Subgroup analyses were conducted by geographical region, study design, year of publication, diabetes ascertainment, type of DM, and adjustments for some variables, and the positive association between DM and risk of EC was consistently observed in each subgroup. Sensitivity analyses also showed that no single study significantly influenced the pooled relative risk. No significant publication bias (P = 0.173) was found. Diabetes mellitus was not positively associated with EC mortality (SRR, 1.23; 95% CI, 0.80-1.90; test for heterogeneity: Q = 11.95, P = 0.035, I(2) = 58.2%). CONCLUSIONS: This meta-analysis of cohort studies suggests that there is a significant association between DM and increased risk of EC incidence but no increased risk of EC mortality.

Pre-pregnancy body mass index moderates the effect of maternal depressive symptoms on small-for-gestational-age infants.

PURPOSE: We aimed to investigate whether the negative effects of maternal depressive symptoms on Small for gestational age (SGA) was moderated by pre-pregnancy body mass index. METHODS: A total of 9,851 women provided self-reported height and pre-pregnancy weight at their first prenatal visit. Pre-pregnancy BMI was categorized according to the BMI cut point ranges for Chinese adults. Depression during pregnancy was assessed by using standardized questionnaires. Demographic characteristics and birth outcomes, including gestational age at birth and birth weight, were collected through the interviews and case history. Multiple regression analysis was used to estimate the relationship between depressive symptoms and SGA among various pre-pregnancy BMI groups. RESULTS: The relationship between depressive symptoms and SGA was inconsistent among three pre-pregnancy BMI groups. The incidence of SGA was positively related with depressive symptoms only among women with pre-pregnancy underweight [odds ratio (OR) 1.89, 95 % confidence interval (CI) 1.12-3.21]. CONCLUSIONS: The negative effect of depressive symptoms during pregnancy on SGA depends on pre-pregnancy BMI.

Blood lead levels during pregnancy and its influencing factors in Nanjing, China.

OBJECTIVE: To investigate the blood lead levels (BLLs) in the duration of pregnancy and 6-12 weeks after delivery, and analyze the influencing factors of BLLs in healthy pregnant women. METHODS: Pregnant women were recruited from September 2009 to February 2010 at the prenatal clinic in Nanjing Maternity and Child Health Care Hospital. Altogether 174 healthy pregnant women without pregnant or obstetric complications or abnormal pregnancy outcomes were enrolled as the gravida group, and 120 healthy non-pregnant women as the control group. BLLs during pregnancy were determined by flame atomic absorption spectroscopy. RESULTS: BLLs in all the three pregnancy trimesters and postpartum were 59.8±24.3, 55.4±20.1, 55.9±19.7, and 67.6±17.4 µg/L, respectively, and the mean BLL in control group was 67.5±21.3 µg/L. BLLs during all the three trimesters were lower in the gravida group than in the control group (P=0.043, 0.021, and 0.028). Furthermore, occupations, nutrients supplementation, and time of house/apartment painted were associated with BLLs in pregnant women. Lead-related occupations, cosmetics use, and living in a house painted less than 1 year before are risk factors of high BLLs among pregnant women, while calcium, iron, zinc, and milk supplements are protective factors. CONCLUSION: Supplementing calcium, iron, zinc, and milk, or avoiding contact with risk factors may help people, especially pregnant women, to reduce lead exposure.

Neurotoxicity and biomarkers of lead exposure: a review.

Appropriate selection and measurement of lead biomarkers of exposure are critically important for health care management purposes, public health decision making, and primary prevention synthesis. Lead is one of the neurotoxicants that seems to be involved in the etiology of psychologies. Biomarkers are generally classified into three groups: biomarkers of exposure, effect, and susceptibility.The main body compartments that store lead are the blood, soft tissues, and bone; the half-life of lead in these tissues is measured in weeks for blood, months for soft tissues, and years for bone. Within the brain, lead-induced damage in the prefrontal cerebral cortex, hippocampus, and cerebellum can lead to a variety of neurological disorders, such as brain damage, mental retardation, behavioral problems, nerve damage, and possibly Alzheimer's disease, Parkinsons disease, and schizophrenia. This paper presents an overview of biomarkers of lead exposure and discusses the neurotoxic effects of lead with regard to children and adults.

Breast milk lead and cadmium levels in suburban areas of Nanjing, China.

OBJECTIVE: To evaluate levels of lead (Pb) and cadmium (Cd) in the breast milk in the second postpartum month, to investigate the relationship between Pb/Cd levels in breast milk and some sociodemographic parameters, and to explore whether these levels affect the infants' physical status or the mothers' psychological status (postpartum depression). METHODS: A cross-sectional study was conducted between November 2009 and December 2010. Altogether 170 healthy mothers were enrolled from Nanjing Maternity and Child Health Care Hospital. The inclusion criteria were: voluntary to participate in this study, healthy, with no chronic disease, breastfeeding in the second postpartum month, living in a suburban but not non-industrial area of Nanjing, and not occupationally exposed to toxic metals. All the mothers completed a questionnaire and were evaluated based on the Edinburgh Postpartum Depression Scale (EPDS) to identify the risk of postpartum depression. Pb and Cd levels in breast milk were determined by inductively coupled plasma mass spectroscopy. The infants of these mothers were examined for their z scores of weight for age, length for age, head circumference for age, and body mass index for age. RESULTS: The median breast milk levels of Pb and Cd were 40.6 µg/L and 0.67 µg/L, respectively. In 164 (96.5%) of the 170 samples, Pb levels were higher than the limit reported by the World Health Organization (> 5 µg/L). Breast milk Cd level was > 1 µg/L in 54 (31.8%) mothers. The mothers with a history of anemia had a higher breast milk Pb level than those without a history of anemia (41.1 µg/L vs. 37.9 µg/L, P = 0.050). The median breast milk Cd level in those who were active and passive smokers during pregnancy was significantly higher than that in non-smokers (0.88 µg/L vs. 0.00 µg/L, P = 0.025). The breast milk Cd level in the mothers not taking iron and vitamin supplements for 2 months postpartum was higher than in those taking the supplements (iron supplement: 0.74 µg/L vs. 0.00 µg/L, P = 0.025; vitamin supplement: 0.78 µg/L vs. 0.00 µg/L, P = 0.005). Breast milk Cd level at the second postpartum month was negatively correlated with the z scores of head circumference (r = - 0.248, P = 0.042) and weight for age at birth (r =- 0.241, P = 0.024) in girls. No correlation was found between the breast milk Pb/Cd levels and the EPDS scores. CONCLUSION: Considering the high levels of Pb and Cd in breast milk in this study, breast milk monitoring programs are necessary.