Jiong Li

Background: Preterm birth (PTB) is a leading cause of infant morbidity and mortality. Gestational temperature variation (TV) may contribute to offspring PTB, but knowledge on PTB subtypes and the role of pregnancy complications remains limited.Methods: We included 18,130 singleton live births from the Jiangsu Birth Cohort (JBC) (2014 - 2022). Daily temperature data were linked to maternal residential addresses. Intra-day and inter-day TV were assessed as the maximum daily diurnal temperature range and consecutive-day mean temperature changes. Logistic regression was used to estimate the associations of gestational TV with PTB and its clinical subtypes (spontaneous PTB (S-PTB), medically indicated PTB (MI-PTB)). Mediation analysis was performed to examine the role of pregnancy complications.Findings: Among 18,130 births, 883 (4.9%) were PTB, including 532 (2.9%) S-PTB and 205 (1.1%) MI-PTB. Each 1℃ increase in second-trimester Temp-inc was associated with higher risk of PTB (OR 1.29, 95% CI 1.06, 1.57). Second-trimester Max-DTR showed subtype heterogeneity (P for heterogeneity = 0.026) and was associated with S-PTB (OR 1.09, 95% CI 1.01, 1.17). Third-trimester TV showed U-shaped associations. Both extremely negative (95th percentile) TV were associated with higher PTB risks (OR range 1.40-2.42), without subtype heterogeneity. Hypertensive disorders of pregnancy, fetal distress, and placenta previa partly mediated third-trimester associations, with stronger mediation for MI-PTB.Interpretation: Extreme TV during the second or third trimester increased the overall risk of PTB and the risks of its two clinical subtypes. Several pregnancy complications mediate these associations, particularly in late pregnancy and for MI-PTB.

Background: Food for special medical purposes (FSMP) may be used during pregnancy to support nutritional management, but its association with subsequent glucose and lipid metabolism remains unclear. Methods: We emulated a target trial using data from pregnant women attending the clinical nutrition outpatient clinic of West China Second University Hospital between July 2024 and September 2025. FSMP use before 28 gestational weeks was compared with no use, and glucose and lipid profiles were measured in blood samples collected after 28 gestational weeks. A clone-censor-weight approach was applied to estimate the per-protocol effect, and weighted linear regression models were used to estimate β coefficients and 95% confidence intervals (CI). Interaction and sensitivity analyses were also conducted.Findings: A total of 2,320 pregnant women were included, including 362 FSMP users and 1,958 non-users. FSMP use was associated with lower fasting blood glucose, although the association was borderline statistically significant after full adjustment (β = -0.071, 95% CI: -0.142 to 0.000; P = 0.051). FSMP use was significantly associated with higher total cholesterol levels (β = 0.154, 95% CI: 0.002 to 0.306; P = 0.048). No significant associations were observed for HDL-C, LDL-C, or triglycerides after full adjustment. Sensitivity analyses showed generally consistent results, and interaction analyses provided no clear evidence of subgroup-specific differences.Interpretation: FSMP use before late pregnancy was associated with modest changes in late-pregnancy fasting glucose and lipid profiles, particularly higher total cholesterol levels. Further studies with larger sample sizes and more detailed dietary information are needed to validate these findings.

Some heavy metals are associated with periodontitis; whereas most of these associations have focused on individual metal, there are no specific studies on the effects of combined heavy metal exposure on periodontitis. We conducted an analysis on the association between urinary heavy metal exposure and periodontitis in participants aged 30 years and older using multiple logistic regression and Bayesian kernel machine regression (BKMR). This analysis was performed on data from the National Health and Nutrition Examination Survey from 2011 to 2014. The study found that using logistic regression, the 4th quartile of urinary lead and molybdenum and the 3rd quartile of urinary strontium were positively associated with periodontitis compared to the reference quartile after adjusting for covariates. Odds ratio (OR) with 95% confidence interval (CI) was 1.738 (1.069–2.826), 1.515 (1.025–2.239), and 1.498 (1.010–2.222), respectively. The 3rd and 4th quartiles of urinary cobalt were negatively associated with periodontitis, and their ORs and 95% CIs were 0.639 (0.438–0.934) and 0.571 (0.377–0.964), respectively. The BKMR model showed that urinary barium, lead, and molybdenum were positively associated with periodontitis in a range of concentrations and urinary cobalt, manganese, tin, and strontium were negatively correlated with periodontitis. Furthermore, the overall association between urinary heavy metals and periodontitis was positive. Our study provides evidence for an association between exposure to multiple urinary heavy metals and periodontitis. However, further longitudinal studies are needed to explore the specific mechanisms involved.

Background and Objectives: Previous epidemiological studies show that high maternal alcohol intake during pregnancy is related to offspring mortality, however, the association of high maternal alcohol intake before conception with stillbirth and infant mortality is less clear. This study...