Objective To project the temporal trend and spatial distribution of excess stillbirths attributable to rising temperatures in China under different climate change scenarios, so as to provide a reference for the rational allocation of health resources. Methods The Coupled Model Intercomparison Project (CMIP) is an important tool for climate change research, providing projections of climate variables such as atmospheric temperature. The Coupled Model Intercomparison Project Phase 6 (CMIP6) provides temperature projections under different shared socioeconomic pathways (SSPs). In this study, 2015 was used as the baseline period to calculate temperature changes under the SSP126, SSP245 and SSP585 scenarios (denoting the sustainable pathway and low radiative forcing, the intermediate pathway and intermediate radiative emissions, and the traditional fossil fuel-dominated pathway and high radiative forcing, respectively) from 2021 to 2100. High-resolution stillbirths were calculated by integrating the number of stillbirths in China from the United Nations and the high-resolution number of pregnancies from the WorldPop. Based on temperature changes, high-resolution stillbirths and the established exposure-response relationship (RR=1.05, 95% CI:1.01-1.08), the number of excess stillbirths attributable to rising temperatures was calculated. Results By the end of this century, under the SSP126, SSP245 and SSP585 scenarios, the number of excess stillbirths attributable to rising temperatures in China was 9 353 (95% CI:2 082-13 794), 13 643 (95% CI:3 006-20 340), and 30 817 (95% CI:7 072-44 778) per year, respectively. The number of excess stillbirths attributable to rising temperatures showed an increasing trend over time, with the majority of excess stillbirths occurring in the third topographic ladder. Conclusion Rising temperatures will lead to an increased burden of stillbirths in China, especially in the third topographic ladder. Mitigating climate change would therefore safeguard maternal and newborn health.

Objective To investigate the correlation between prenatal Particulate Matter 2.5 (PM_2.5) exposure and multiple growth parameters in early childhood. Methods A total of 1,666 children from Peking University Birth Cohort in Tongzhou (PKUBC-T) were selected, and their length and weight data were recorded during 7 follow-ups from 1 month to 24 months of age. The velocity, amplitude and peak parameters of Body Mass Index (BMI) and Weight for Length (WFL) were used to assess child growth. Machine learning models were used to calculate the average daily PM_2.5 concentrations during pregnancy. Generalized linear regression and generalized linear mixed-effects models were used for the association between prenatal PM_2.5 concentration and growth indicators in children. Results After adjusting for covariates, every 10μg/m³ increase of maternal PM_2.5 exposure during pregnancy was associated with decreased growth velocities of BMI-Z and WFL-Z in children aged 0~2 years by 0.06 (95% CI:-0.12, -0.01, P=0.029) and 0.11 (95% CI:-0.17, -0.05, P=0.001) respectively, reduced growth amplitudes by 0.19 (95% CI:-0.33, -0.05, P=0.010) and 0.32 (95% CI:-0.47, -0.17, P<0.001) respectively, as well as delayed peak month by 4.19 months (95% CI:1.88, 6.51;P<0.001), increased WFL peak by 0.62 kg/m (95% CI:0.03, 1.21;P=0.038). These associations remained significant after excluding those preterm birth and low birth weight children. Conclusion Maternal exposure to PM_2.5 during pregnancy inhibited growth velocities and amplitudes in children aged 0~2 years, increased and delayed the WFL growth peak, indicating that prenatal PM_2.5 exposure may influence the growth of children.

Objective To examine the temporal trends and spatial distribution characteristics of fertility rate among women of childbearing age across 31 provincial-level administrative regions in China from 2008 to 2022. Methods Statistical data related to fertility rates in 31 provincial-level administrative regions (excluding Hong Kong, Macao and Taiwan regions of China) in China from 2008 to 2022 were collected. Descriptive analysis was conducted in both spatial and temporal dimensions, spatial autocorrelation analysis was used to explore the spatial aggregation characteristics and patterns of fertility rates by region. Results Fertility rate among women of childbearing age in China remained persistently low from 2008 to 2022, accompanied by a notable phenomenon of delayed childbearing among the childbearing age population. The spatial pattern exhibited a gradual decrease from the south to the north. There is a positive spatial autocorrelation of fertility rates with distinct clustering patterns across regions. Conclusion Fertility rate among women of childbearing age in China continues to be persistently low, and it is expected that the fertility will remain at an extremely low rate for a long time in the future. In order to promote the long-term balanced population development, region-specific personalized suggestions could be put forward according to the distinct spatial patterns, and international experience could be drawn to foster a fertility-friendly social environment.

Objective To explore the correlation and differential effects of paternal smoking, alcohol consumption in three months before pregnancy with spontaneous abortion, so as to provide evidence for pre-pregnancy health guidance. Methods A case-control study was conducted in the Anhui Province pilot site of abortion monitoring under the birth and birth defects surveillance sub-project of the comprehensive cancer prevention and application promotion project. All recorded cases of spontaneous abortion and controls (full-term normal live births) collected from January 2020 to December 2024 were included. A unified registration form specific to the project was used to record maternal information, paternal information, pregnancy history, current pregnancy details, as well as major diseases and environmental risk factors from three months prior to conception until pregnancy termination. All information was uniformly entered into the Key Regions Birth and Birth Defect Surveillance Management Module of the China Disease Control and Prevention Information System. Results A total of 1 411 participants were included (737 controls, 674 spontaneous abortion cases). Paternal smoking and alcohol consumption rates in three months before pregnancy were 15.6% and 24.8%, respectively. Multivariate logistic regression analysis, after adjusting for covariates such as maternal age, education level, gravidity, and parity, showed that compared with the group with neither paternal smoking nor alcohol consumption in three months before pregnancy, the risk of spontaneous abortion was significantly increased in the smoking only group (OR=4.97, 95%CI=1.70, 14.50), the alcohol consumption only group (OR=1.68, 95%CI=1.04, 2.72), and the group with both smoking and alcohol consumption (OR=5.34, 95%CI=3.12, 9.12). Compared with non-smokers, the OR values for smoking 1-9 cigarettes and ≥10 cigarettes per day were 3.05 and 9.96, respectively. Conclusion The findings suggest that paternal smoking and alcohol consumption before pregnancy can significantly increase the risk of spontaneous abortion in their spouses. Health education emphasizing smoking and alcohol cessation for both partners during the preconception period should be strengthened.

Objective To explore the value of total testosterone (TT) as a surrogate index in the diagnosis of hyperandrogenism in patients with polycystic ovary syndrome (PCOS), and analyze the optimal cutoff value of TT to improve the positive diagnostic rate. Methods 279 PCOS patients who met the Rotterdam criteria were enrolled in this hospital, and the diagnostic rate of hyperandrogenism was calculated with TT as the reference index. Androstenedione (AND), sex hormone-binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEAS) and free testosterone index (FAI) were used as diagnostic criteria, and the diagnostic rates of hyperandrogenism were calculated based on AND, DHEAS, SHBG and FAI, respectively. Multiple group and pairwise consistency comparisons were performed to compare the diagnostic value of TT with other androgen indices. The sensitivity and specificity of TT in diagnosing PCOS hyperandrogenism were calculated using ROC curves, and the optimal diagnostic cutoff value of TT was analyzed. Results When using SHBG as the gold standard to re-evaluate the cutoff diagnostic value of TT, the sensitivity was 73.3%, the specificity was 77.1%, and the maximum Yoden index was 0.504. Conclusion The clinical diagnostic threshold of HA was adjusted from TT > 0.73 ng/ml to TT > 0.53 ng/ml, which could better improve the accuracy of clinical diagnostic rate.

Objective To observe the effects of YangLuanfang (YLF) on SIRT3/ FOXO3-a and PLA2/COX2 signaling pathways in ovarian tissue of rats with diminished ovarian reserve (DOR), and explore the effect and mechanism of YLF on improving ovarian reserve function in rats with DOR. Methods SD rats were randomly divided into control group and model group. DOR model rats were made by intraperitoneal injection of vinylcyclohexene dioxide (VCD). The successful DOR rats were randomly divided into model group, YLF low-dose (YLF-L) group, YLF middle-dose (YLF-M) group, YLF high-dose (YLF-H) group and progynova (BJL) group. Each group was given corresponding drugs by gavage for 15 days. The indexes of gonads (ovaries and uterus) were compared in each group, and observe the pathological morphological changes of ovarian tissues by HE staining. Serum FSH, LH and AMH levels were detected. Western blot was used to detect the expression levels of SIRT3,FOXO3a,PLA2 and COX2 proteins in ovarian tissues. PCR was used to detect the mRNA expression levels of SIRT3, FOXO3a, PLA2, COX2, SOD,GSH-Px and CAT in ovarian tissue. Results Compared with the control group, the index of ovary and uterus in the model group decreased (P<0.05), the levels of serum FSH,LH and the FSH/LH ratio increased (P<0.05), AMH level decreased (P<0.05), and the expression levels of SIRT3, FOXO3a, PLA2, COX2 protein and mRNA, SOD, GSH-Px, and CAT mRNA in ovarian tissue decreased (P<0.05). Compared with the model group, the moderate to high doses of YLF improved the ovary pathological morphology of DOR rats, increased the ovarian and uterine index (P<0.05), decreased the levels of serum FSH, LH and the FSH/LH ratio (P<0.05), increased the AMH level (P<0.05), and increased the expressions of SIRT3, FOXO3a, PLA2, COX2 protein and mRNA, and the mRNA of SOD, GSH-Px and CAT in ovarian tissue (P<0.05). Conclusion YLF may improve the activity of antioxidant enzymes, regulate endocrine function, and alleviate ovarian damage induced by VCD by regulating SIRT3/FOXO3a and PLA2/COX2 signaling pathways.