Prevalence and influencing factors of anemia among pregnant women across first, second and third trimesters of pregnancy in monitoring areas, from 2016 to 2020: a population-based multi-center cohort study.

OBJECTIVE: To assess the prevalence of anemia among pregnant women across their entire pregnancy and the factors affecting it in the monitoring areas. METHODS: A total of 108,351 pregnant women who received antenatal health care and delivered from January 1, 2016 to December 31, 2020 in 15 monitoring counties of 8 provinces in the Maternal and Newborn Health Monitoring Program (MNHMP) of National Center for Women and Children's Health (NCWCH) were selected as the study subjects. The anemia status among the subjects across their first, second and third trimester of pregnancy and the influencing factors were analyzed. RESULTS: From 2016 to 2020, the prevalence of anemia at any stage during pregnancy in the monitoring areas was 43.59%. The prevalence of anemia among pregnant women across all three trimesters was 3.95%, and the prevalence of mild and moderate-to-severe anemia was 1.04% and 2.90%, respectively. Protective factors were living in the northern area (OR = 0.395) and being a member of an ethnic minority (OR = 0.632). The risk factors were residing in rural areas (OR = 1.207), with no more than junior high school education (OR = 1.203), having ≥ 3 gravidities (OR = 1.195) and multiple fetuses (OR = 1.478). CONCLUSIONS: Although the prevalence of anemia among pregnant women across all trimesters in the monitoring area was low, the severity of anemia was high. Since the prevalence of anemia among pregnant women across their entire pregnancy in the monitoring area is affected by many different factors, more attention should be paid to pregnant women living in rural areas, with low literacy, ≥ 3 gravidities and multiple fetuses for early intervention.

Prevalence and risk factors for depressive and anxiety symptoms in middle-aged Chinese women: a community-based cross-sectional study.

BACKGROUND: Depression and anxiety have become main public health concerns globally. However, risk factors for depression and anxiety remain unclear. This study was to examine the prevalence and risk factors of depressive and anxiety symptoms in middle-aged Chinese women. METHODS: This cross-sectional study, conducted in 2018, included 7,727 women aged 40-60 years from the eastern, central and western regions of China. Depressive and anxiety symptoms were determined by the Patient Health Questionnaire-9 and the Generalized Anxiety Disorders-7, respectively. Logistic regression models were used to estimate odds ratios (ORs) for depressive and anxiety symptoms in relation to sociodemographic, lifestyle and menopausal factors. RESULTS: Among all participants, 19.5% (1 422/7 275) and 14.2% (1 035/7 275) of participants experienced depressive and anxiety symptoms, respectively. The multivariable logistic regression models showed that age, household income, regular physical activity, chronic diseases, menopausal status, vasomotor symptoms, somatic symptoms and urogenital symptoms were associated with depressive symptoms, while place of residence, regular physical activity, chronic diseases, vasomotor, somatic and urogenital symptoms were associated with anxiety symptoms. CONCLUSION: Depressive and anxiety symptoms were common among middle-aged Chinese women, and certain sociodemographic, lifestyle and menopausal symptoms have an important impact on the risk of depressive and anxiety symptoms.

Gestational PM2.5 exposure may increase the risk of small for gestational age through maternal blood pressure and hemoglobin: A mediation analysis based on a prospective cohort in China, 2014-2018.

BACKGROUND: Maternal gestational PM2.5 exposure was associated with small for gestational age (SGA). Identifying potential mediating factors may help design preventive strategies to reduce this risk. OBJECTIVE: This study aimed to explore the roles of maternal blood pressure and hemoglobin may play in the PM2.5 exposure and SGA relationship among 117,162 births in 16 counties across China during 2014-2018. METHODS: Daily PM2.5 concentration was collected from China National Environmental Monitoring Center. According to maternal residency during pregnancy, the PM2.5 exposure for each trimester and the whole pregnancy was assessed using an inverse-distance weighting approach. Repeated measurements of maternal blood pressure and hemoglobin during pregnancy were collected for each woman. We estimated the total effect of gestational PM2.5 exposure on SGA, and further tested the mediation effects of maternal blood pressure and hemoglobin concentration during pregnancy. RESULTS: Of 117,162 included mother-infant pairs, 11,361 (9.7 %) were SGA. The odds ratios of SGA associated with PM2.5 exposure (per 10 µg/m3 increase) in the second trimester and the whole pregnancy were 1.023 (95 % CI: 1.009, 1.037) and 1.024 (1.001, 1.048), respectively. We identified the independent mediating effect of blood pressure and hemoglobin in the second and third trimesters, with the proportion of mediation ranging from 1.64 % to 5.78 % and 2.40 % to 8.70 %, respectively. When considering the mediators jointly, we found a stronger mediating effect with a proportion of mediation ranging from 3.93 % to 13.69 %. DISCUSSION: Increases in maternal blood pressure and hemoglobin in the second and third trimesters can independently and jointly mediate the effects of gestational PM2.5 exposure on SGA. Monitoring and managing maternal blood pressure and hemoglobin during prenatal care may constitute a promising avenue to reducing SGA risk associated with gestational PM2.5 exposure.

Real-world effectiveness of primary screening with high-risk human papillomavirus testing in the cervical cancer screening programme in China: a nationwide, population-based study.

BACKGROUND: Randomized controlled trials have shown a higher sensitivity and longer negative predictive value of high-risk human papillomavirus (HPV) testing than cytology for cervical cancer screening; however, little is known about the effectiveness of HPV testing in middle-income countries. Understanding the characteristics of HPV testing may increase the priority of HPV testing in health policies. The study aims to evaluate the effectiveness of HPV testing in the national cervical cancer screening programme in China. METHODS: We performed a nationwide, population-based study using individual data from the national cervical cancer screening programme in rural China between 2015 and 2017. The analyses included 1,160,981 women aged 35-64 years who underwent cytology alone or high-risk HPV testing with cytology or genotyping triage. The main outcome was cervical intraepithelial neoplasia 2 or worse (CIN2+). We used multivariate logistic regressions and performed sensitivity analyses with propensity score matching to compare the screening positive, colposcopy referral, detection rate, and positive predictive value (PPV). RESULTS: The screening positive rates for HPV testing and cytology were 10.1% and 4.0%, respectively. The per protocol colposcopy referral rate of HPV testing was significantly lower than that of cytology (3.5% vs 4.0%), and this difference was mostly due to the low referral threshold of cytology (≥ASC-US). Overall, HPV testing detected more CIN2+ (5.5 vs. 4.4 per 1000, adjusted odds ratio [aOR]=1.18, 95% confidence interval 1.11-1.25) and had a higher PPV (13.8% vs 10.9%, aOR 1.29, 95% CI 1.21-1.37) than cytology. The colposcopy referrals of HPV testing in comparison to cytology differed by income status; it significantly increased in lower-middle-income areas (3.7% vs 3.1%, aOR 1.21, 95% CI 1.17-1.25) and significantly decreased in upper-middle-income areas (3.4% vs 4.9%, aOR 0.69, 95% CI 0.67-0.71). Sensitivity analyses demonstrated the reliability and robustness of the results. CONCLUSIONS: The introduction of HPV testing could improve both the CIN2+ detection rate and efficiency of cervical cancer screening programme, supporting the introduction of primary screening with high-risk HPV testing in China. Further study is needed to investigate the long-term effect of this change.

Current status of antenatal care of pregnant women-8 provinces in China, 2018.

BACKGROUND: Antenatal care (ANC) played a crucial role in ensuring maternal and child safety and reducing the risk of complications, disability, and death in mothers and their infants. The objective of this study was to evaluate the current status of ANC emphasizing the number, timing, and content of examinations on a national scale. METHODS: The data was collected from maternal and newborn's health monitoring system at 8 provinces in China. After ethical approval, all pregnant women registered in the system at their first prenatal care visit, we included 49,084 pregnant women who had delivered between January 1, 2018 and December 31, 2018. Descriptive statistics of all study variables were calculated proportions and chi-square for categorical variables. RESULTS: Of the 49,084 women included in this study, the mean number of ANC visits was 6.95 ± 3.45. By percentage, 78.79% women received ANC examinations at least five times, 39.93% of the women received ANC examinations at least eight times and 16.66% of the women received ANC examinations at least 11 times. The proportion of first ANC examination in first trimester was 61.87%. The percentage of normative ANC examinations and the percentage of qualified ANC examinations were 30.98 and 8.03% respectively. Only 49.40% of the total women received all six kinds of examination items in first ANC examination: 91.47% received a blood test, 91.62% received a urine test, 81.56% received a liver function examination, 80.52% received a renal function examination, 79.07% received a blood glucose test, and 86.66% received a HIV/HBV/syphilis tests. 50.85% women received the first ANC examination in maternal and child health care (MCH) institutions, 14.07% in a general hospital, 18.83% in a township hospital, 13.15% in a community health services center, and 3.08% in an unspecified place. The proportion of women who received each of the ANC examination items in community health services center was the highest, but that in the MCH institutions was the lowest. CONCLUSIONS: There is a big difference between the results of this study and the data in official reports, this study found the current status of antenatal care is not optimal in China, findings from this study suggest that the systematization, continuity and quality of ANC examinations need to be improved.

Association of Perceived Threat, Negative Emotions, and Self-Efficacy With Mental Health and Personal Protective Behavior Among Chinese Pregnant Women During the COVID-19 Pandemic: Cross-sectional Survey Study.

BACKGROUND: COVID-19 is an emerging infectious disease that has created health care challenges worldwide. Pregnant women are particularly affected by this disease. OBJECTIVE: The aims of this study are to assess the levels of perceived threat (susceptibility, severity, impact), negative emotions (fear, worry), and self-efficacy of pregnant women in China related to COVID-19 and to examine their associations with mental health (depression and anxiety) and personal protective behavior (wearing a face mask). METHODS: A total of 4087 pregnant women from China completed a cross-sectional web-based survey between March 3 and 10, 2020. RESULTS: The prevalence of probable depression and anxiety was 48.7% (1989/4087) and 33.0% (1347/4087), respectively; 23.8% participants (974/4087) reported always wearing a face mask when going out. Of the 4087 participants, 32.1% (1313) and 36.4% (1490) perceived themselves or their family members to be susceptible to COVID-19 infection, respectively; 3216-3518 (78.7%-86.1%) agreed the disease would have various severe consequences. Additionally, 2275 of the 4087 participants (55.7%) showed self-efficacy in protecting themselves from contracting COVID-19, and 2232 (54.6%) showed efficacy in protecting their family members; 1303 (31.9%) reported a high level of fear of the disease, and 2780-3056 (68.0%-74.8%) expressed worry about various aspects of COVID-19. The results of the multivariate multinominal logistic regression analyses showed that perceived severity, perceived impact, fear, and worry were risk factors for probable depression and anxiety, while self-efficacy was a protective factor. The results of the multivariate logistic regression analysis showed that perceived susceptibility was associated with always wearing a face mask. CONCLUSIONS: Chinese pregnant women showed high levels of mental distress but low levels of personal protective behavior during the COVID-19 pandemic. Interventions are needed to promote the mental health and health behavior of pregnant women during the pandemic.

Social, Cognitive, and eHealth Mechanisms of COVID-19-Related Lockdown and Mandatory Quarantine That Potentially Affect the Mental Health of Pregnant Women in China: Cross-Sectional Survey Study.

BACKGROUND: Although lockdown and mandatory quarantine measures have played crucial roles in the sharp decrease of the number of newly confirmed/suspected COVID-19 cases, concerns have been raised over the threat that these measures pose to mental health, especially the mental health of vulnerable groups, including pregnant women. Few empirical studies have assessed whether and how these control measures may affect mental health, and no study has investigated the prevalence and impacts of the use of eHealth resources among pregnant women during the COVID-19 outbreak. OBJECTIVE: This study investigated (1) the effects of lockdown and mandatory quarantine on mental health problems (ie, anxiety and depressive symptoms), (2) the potential mediation effects of perceived social support and maladaptive cognition, and (3) the moderation effects of eHealth-related factors (ie, using social media to obtain health information and using prenatal care services during the COVID-19 pandemic) on pregnant women in China. METHODS: An online cross-sectional survey was conducted among 19,515 pregnant women from all 34 Chinese provincial-level administrative regions from February 25 to March 10, 2020. RESULTS: Of the 19,515 participants, 12,209 (62.6%) were subjected to lockdown in their areas of residence, 737 (3.8%) were subjected to mandatory quarantine, 8712 (44.6%) had probable mild to severe depression, 5696 (29.2%) had probable mild to severe anxiety, and 1442 (7.4%) had suicidal ideations. Only 640 (3.3%) participants reported that they used online prenatal care services during the outbreak. Significant sociodemographic/maternal factors of anxiety/depressive symptoms included age, education, occupation, the area of residence, gestational duration, the number of children born, complication during pregnancy, the means of using prenatal care services, and social media use for obtaining health information. Multiple indicators multiple causes modeling (χ214=495.21; P<.05; comparative fit index=.99; nonnormed fit index=.98; root mean square error of approximation=.04, 90% CI 0.038-0.045) showed that quarantine was directly and indirectly strongly associated with poor mental health through decreased perceived social support and increased maladaptive cognition (B=.04; ß=.02, 95% CI 0.01-0.02; P=.001), while lockdown was indirectly associated with mental health through increased social support and maladaptive cognition among pregnant women (B=.03; ß=.03, 95% CI 0.02-0.03; P=.001). Multigroup analyses revealed that the use of social media for obtaining health information and the means of using prenatal care services were significant moderators of the model paths. CONCLUSIONS: Our findings provide epidemiological evidence for the importance of integrating mental health care and eHealth into the planning and implementation of control measure policies. The observed social and cognitive mechanisms and moderators in this study are modifiable, and they can inform the design of evidence-based mental health promotion among pregnant women.

A nationally quasi-experimental study to assess the impact of partial organized breast and cervical cancer screening programme on participation and inequalities.

BACKGROUND: Organized breast and cervical cancer screening programme could only provide services at no cost for a fraction of socioeconomic-deprived women in China and other low-resource countries, however, little evidence exists for whether such a programme effectively affect the participation and inequalities at the population level. METHODS: We used individual-level data from a nationally cross-sectional survey in 2014-2015 for breast and cervical cancer screening participation. Data for intervention and comparison grouping were from 2009 to 2014 national breast and cervical cancer screening programme, and counties covered by the programme were divided into intervention group. We assessed the impact of the intervention on the participation rates and the magnitude of inequalities with two approaches: multivariable multilevel logistic regressions adjusting for individual- and region-level covariates; and a difference analysis combined with propensity score matching that estimated the average intervention effect. RESULTS: Of 69,875 included women aged 35-64 years, 21,620 were classified into the intervention group and 43,669 into the comparison group for breast cancer screening; and 31,794 into the intervention group, and 33,682 into the comparison group for cervical cancer screening. Participation rate was higher in intervention group than comparison group for breast cancer screening (25.3, 95% confidential interval [CI], 22.8-27.7%, vs 19.1, 17.4-20.7%), and cervical cancer screening (25.7, 23.8-27.7%, vs 21.5, 19.6-23.5%), respectively. Intervention significantly increased the likelihood of participation for both breast cancer and cervical cancer screening in overall women, rural women and urban women, whereas the effect was significantly higher in rural women than urban women. The average intervention effect on the participation rate was an increase of 7.5% (6.7-8.2%) for breast cancer screening, and 6.8% (6.1-7.5%) for cervical cancer screening, respectively. The inequalities were significantly decreased by 37-41% (P < 0.001) between rural and urban, however, were slightly decreased or even increased in terms of age, education status, and household income. CONCLUSIONS: Organized breast and cervical cancer screening programme targeting for a fraction of women could increase the participation rates at population level, however, it could not significantly affect socioeconomic-introduced inequalities. Further studies are need to conduct time-series analyses and strengthen the causal correlation.

Fertility Intentions Among Reproductive-Age Women - Three Provinces, China, 2023.

What is already known about this topic?: Low fertility rates have become the most important risk affecting the balanced development of the population in China. What is added by this report?: About 80.0% of childless women had fertility intentions, 31.9% of women with one child and 11.3% of women with two children intended to have a second and third child, respectively. Women with one child who had an agricultural Hukou, were younger than 30 years old, were remarried, and had received a deduction or reimbursement for childbirth expenses during their first delivery were more willing to have a second child. Women with two children who had an agricultural Hukou and a upper-middle personal income, were self-employed, and had two daughters were more willing to have a third child. What are the implications for public health practice?: In China, women's willingness to have more children is not optimistic. To increase their desire for more children, creating a more favorable fertility environment for reproductive-age women and providing more preferential fertility policies for pregnant women will be necessary.

Changes in Maternal Socio-Demographic Characteristics and Pregnancy Outcomes Across Monitoring Regions - Six Provinces, China, 2016-2022.

What is already known about this topic?: In recent years, there has been a significant increase in the proportion of women of advanced maternal age (AMA), accompanied by a rise in adverse pregnancy outcomes in certain regions of China. What is added by this report?: From 2016 to 2022, there was an observed increase in the proportion of AMA, educational levels, and incidences of preterm birth and low birth weight (LBW) in both primiparous and multiparous women. Concurrently, there was a declining trend in the rate of cesarean deliveries and the incidence of macrosomia among multiparous women. What are the implications for public health practice?: In addition to focusing on health management for AMA individuals, proactive steps should be undertaken to enhance the quality of medical services and promote childbirth at optimal ages, thereby reducing the incidence of adverse pregnancy outcomes.

Heat exposure induced risks of preterm birth mediated by maternal hypertension.

Heat exposure is associated with an increased risk of preterm birth (PTB), with previous work suggesting that maternal blood pressure may play a role in these associations. Here we conducted a cohort study of 197,080 singleton live births across 8 provinces in China from 2015 to 2018. The study first estimated the associations between heat exposure, maternal hypertension and clinical subtypes of PTB, and then quantified the role of maternal hypertension in heat and PTB using mediation analyses. We show that heat exposure (>85th, 90th and 95th percentiles of local temperature distributions) spanning from conception to the 20th gestational week was associated with a 15-21% increase in PTB, and a 20-22% increase in medically indicated PTB. Heat exposure is likely to increase the risk of maternal hypertension and elevated blood pressure. Maternal hypertension mediated 15.7% and 33.9% of the effects of heat exposure (>90th percentile) on PTB and medically indicated PTB, respectively. Based on this large-population study, we found that exposure to heat in early pregnancy can increase the risk of maternal hypertension, thereby affecting the incidence of PTB.

Increased risk of preterm birth due to heat exposure during pregnancy: Exploring the mechanism of fetal physiology.

BACKGROUND: Heat exposure during pregnancy can increase the risk of preterm birth (PTB) through a range of potential mechanisms including pregnancy complications, hormone secretion and infections. However, current research mainly focuses on the effect of heat exposure on pathophysiological pathways of pregnant women, but ignore that maternal heat exposure can also cause physiological changes to the fetus, which will affect the risk of PTB. OBJECTIVE: In this study, we aimed to explore the mediating role of fetal heart rate (FHR) in the relationship between maternal heat exposure and PTB incidence. METHODS: We assigned heat exposure to a multi-center birth cohort in China during 2015-2018, which included all 162,407 singleton live births with several times FHR measurements during the second and third trimesters. We examined the associations between heat exposure, FHR and PTB in the entire pregnancy, each trimester and the last gestational month. The inverse odds ratio-weighted approach applied to the Cox regression was used to identify the mediation effect of heat exposure on PTB and its clinical subtypes via FHR. FINDINGS: Exposure to heat significantly increased the risk of PTB during the third trimester and the entire pregnancy, hazard ratios and 95 % CIs were 1.266 (1.161, 1.379) and 1.328 (1.218, 1.447). Heat exposure during the third trimester and entire pregnancy increased FHR in the third trimester by 0.24 bpm and 0.14 bpm. The proportion of heat exposure mediated by FHR elevation on PTB and its subtype ranged from 3.68 % to 24.06 %, with the significant mediation effect found for both medically indicated PTB and spontaneous PTB. CONCLUSIONS: This study suggests that heat exposure during pregnancy has an important impact on fetal health, and FHR, as a surrogate marker of fetal physiology, may mediate the increased risk of PTB caused by extreme heat. Monitoring and managing physiological changes in the fetus would constitute a promising avenue to reduce adverse birth outcomes associated with maternal heat exposure.

Knowledge of Cervical Cancer and HPV, and Willingness to Receive HPV Vaccination Among 20-45-Year-Old Women - Six Provinces, China, 2018.

What is already known about this topic?: Cervical cancer is a significant public health problem with approximately 570,000 cases and 311,000 deaths occurring in 2018 globally. It is imperative to raise awareness of cervical cancer and human papillomavirus (HPV). What is added by this report?: Compared to previous studies, this is one of the largest cross-sectional studies of cervical cancer and HPV in Chinese adult females in recent years. We found that knowledge level of cervical cancer and HPV vaccine was still inadequate among women aged 20-45 years old, and the willingness to receive HPV vaccination was highly associated with knowledge level. What are the implications for public health practice?: Intervention programs should aim to improve awareness and knowledge about cervical cancer and HPV vaccines, primarily focusing on women of lower socio-economic status.

Exploration of the preterm birth risk-related heat event thresholds for pregnant women: a population-based cohort study in China.

Background: Heat events increase the risk of preterm birth (PTB), and identifying the risk-related event thresholds contributes to developing early warning system for pregnant women and guiding their public health response. However, the event thresholds that cause the risk remain unclear. We aimed to investigate the effects of heat events defined with different intensities and durations on PTB throughout pregnancy, and to determine thresholds for the high-risk heat events. Methods: Using a population-based birth cohort data, we included 210,798 singleton live births in eight provinces in China during 2014-2018. Daily meteorological variables and inverse distance weighted methods were used to estimate exposures at a resolution of 1 km × 1 km. A series of cut off temperature intensities (50th-97.5th percentiles, or 18 °C-35 °C) and durations (at least 1, 2, 3, 4 or 5 consecutive days) were used to define the heat events. Cox regression models were used to estimate the effects of heat events on PTB in various gestational weeks during the entire pregnancy, and event thresholds were determined by calculating population attributable fractions. Findings: The hazard ratios of heat event exposure on PTB ranged from 1.07 (95% CI: 1.00, 1.13) to 1.43 (1.15, 1.77). Adverse effects of heat event exposure were prominently detected in gestational week 1-4, week 21-32 and the four weeks before delivery. The heat event thresholds were determined to be daily maximum temperature at the 90th percentile of the distribution or 30 °C lasting for at least one day. If pregnant women were able to avoid the heat exposures from the early warning systems triggered by these thresholds, approximately 15% or 17% of the number of total PTB cases could have been avoided. Interpretation: Exposure to heat event can increase the risk of PTB when thermal event exceeds a specific intensity and duration threshold, particularly in the first four gestational weeks, and between week 21 and the last four weeks. This study provides compelling evidence for the development of heat-health early warning systems for pregnant women that could substantially mitigate the risk of PTB. Funding: National Key R&D Program of China (No. 2018YFA0606200), National Natural Science Foundation of China (No. 42175183), Sanming Project of Medicine in Shenzhen (No. SZSM202111001).

Relationship between Maternal Postpartum Intention to Breastfeed and Actual Breastfeeding Duration - Four Provinces, China, 2015-2017.

What is already known about this topic?: Several studies have reported that maternal antenatal intention to breastfeed is a strong predictor of actual breastfeeding duration. However, little research has investigated whether maternal postpartum intention also extends breastfeeding duration. What is added by this report?: Maternal postpartum intention to breastfeed was a protective factor for extending actual breastfeeding duration after controlling potential confounders. What are the implications for public health practice?: It is crucial to address and promote intrinsic and extrinsic factors that influence a mother's intention to breastfeed after delivery, thereby extending the actual breastfeeding duration.

Effects of Social Media Use for Health Information on COVID-19-Related Risk Perceptions and Mental Health During Pregnancy: Web-Based Survey.

BACKGROUND: Social media has become an important source of health information during the COVID-19 pandemic. Very little is known about the potential mental impact of social media use on pregnant women. OBJECTIVE: This study aims to examine the association between using social media for health information and risk perception for COVID-19, worry due to COVID-19, and depression among pregnant women in China. METHODS: A total of 4580 pregnant women were recruited from various provinces of China. The participants completed a cross-sectional, web-based survey in March 2020. RESULTS: More than one-third (1794/4580, 39.2%) of the participants reported always using social media for obtaining health information. Results of structural equation modeling showed that the frequency of social media use for health information was positively associated with perceived susceptibility (ß=.05; P<.001) and perceived severity (ß=.12; P<.001) of COVID-19, which, in turn, were positively associated with worry due to COVID-19 (ß=.19 and ß=.72, respectively; P<.001). Perceived susceptibility (ß=.09; P<.001), perceived severity (ß=.08; P<.001), and worry due to COVID-19 (ß=.15; P<.001) all had a positive association with depression. Bootstrapping analysis showed that the indirect effects of frequency of social media use for health information on both worry due to COVID-19 (ß=.09, 95% CI 0.07-0.12) and depression (ß=.05, 95% CI 0.02-0.07) were statistically significant. CONCLUSIONS: This study provides empirical evidence on how social media use for health information might have a negative impact on the mental health of pregnant women. Interventions are needed to equip this population with the skills to use social media properly and with caution.

Age-specific effectiveness of primary human papillomavirus screening versus cytology in a cervical cancer screening program: a nationwide cross-sectional study.

BACKGROUND: Primary human papillomavirus (HPV) screening is recommended for the detection of cervical intraepithelial neoplasia (CIN) in the general population; however, the triage for HPV-positive women remains a challenge. This study aimed to evaluate the age-specific effectiveness of primary HPV screening versus primary cytology screening for identifying optimal strategies for women of different ages. METHODS: The dataset of the prevalence round screening was derived from the National Cervical Cancer Screening Program in China. Primary cervical screening protocols included cytology only, HPV testing with cytology triage, and HPV testing with HPV-16/18 genotyping plus cytology triage. The primary outcomes were age-specific detection rate, colposcopy referral rate and positive predictive value (PPV) for CIN2+. Multivariate Poisson regression was used to evaluate the relative effectiveness of HPV testing and cytology according to age groups. The I2 statistic with a random-effect model was used to test the heterogeneity in relative effectiveness of HPV testing versus cytology between age groups. RESULTS: This study included 1,160,981 women. HPV testing with HPV-16/18 genotyping plus cytology triage significantly increased the CIN2+ detection by 36% (rate ratio [RR]: 1.36, 95% confidential interval [CI] 1.21-1.54) for women aged 35-44 years and by 34% (RR: 1.34, 95% CI 1.20-1.51) for women aged 45-54 years compared with cytology only. HPV testing with cytology triage had similar CIN2+ detection rate compared with cytology only. The PPVs were substantially increased for both HPV testing groups. Among women aged 55-64 years old, HPV testing with HPV-16/18 genotyping plus cytology triage increased the colposcopy referral rate by 19% (RR 1.19, 95% CI 1.10-1.29) compared with cytology only, but did not increase the CIN2+ detection (1.09, 0.91-1.30). The effectiveness of HPV testing with cytology triage did not change in older women. The between-age-group heterogeneity in the effectiveness was statistically significant for HPV testing with HPV-16/18 genotyping plus cytology triage versus cytology only. CONCLUSIONS: Our results suggested that the effectiveness of primary HPV screening with different triage strategies differed among age groups. HPV testing with HPV-16/18 genotyping plus cytology triage could be used for women aged 35-54 years to detect more lesions, and HPV testing with cytology triage could balance the CIN2+ detection and the number of colposcopies for women aged 55-64 years. Longitudinal data including both prevalence and incidence screening rounds are warranted to assess age-specific triage strategies.

Effects of extreme temperature on the risk of preterm birth in China: A population-based multi-center cohort study.

Background: Extreme temperatures are associated with the risk of preterm birth (PTB), but evidence on the effects of different clinical subtypes and across different regions is limited. We aimed to evaluate the effects of maternal exposure to extreme temperature on PTB and its clinical subtypes in China, and to identify effect modification of regional factors in dimensions of population, economy, medical resources and environmental factors. Methods: This was a prospective population-based cohort of 210,798 singleton live births from 16 counties in eight provinces across China during 2014-2018. We used an extended Cox regression with time-varying variables to evaluate the effects of extreme heat and cold on PTB and its subtypes in the entire pregnancy, each trimester, the last gestational month and week. Meta-analysis and meta-regression were conducted to estimate the pooled effects of each city and effect modification by regional characteristics. Findings: Exposure to heat and cold during the entire pregnancy significantly increased the risk of PTB. The effects varied with subtypes, for medically indicated and spontaneous PTB, hazard ratios were 1·84 (95% CI: 1·29, 2·61) and 1·50 (95% CI: 1·11, 2·02) for heat, 2·18 (95% CI: 1·83, 2·60) and 2·15 (95% CI: 1·92, 2·41) for cold. The associations were stronger for PTB less than 35 weeks than those during weeks 35-36. The effects varied across locations, and GDP per capita (ß=-0·16) and hospital beds per 1000 persons (ß=-0·25) were protective factors for the effects. Interpretation: Extreme temperature can increase the risk of medically indicated and spontaneous PTB, and higher regional socio-economic status may moderate such effects. In the context of climate change, such findings may have important implications for protecting the health of vulnerable groups, especially newborns. Funding: National Key R&D Program of China (2018YFA0606200), National Natural Science Foundation of China (42175183), Strategic Priority Research Program of the Chinese Academy of Sciences (XDA20030302), National Natural Science Foundation of China (42071377).

Incidence and Risk Factors of Hypertensive Disorders of Pregnancy - 8 Provinces, China, 2014-2018.

What is already known about this topic? As a major cause of maternal and neonatal mortality and morbidity, hypertensive disorders of pregnancy (HDP) are a global public health problem affecting maternal and children's health. What is added by this report?The incidence of HDP was 6.40% among 277,632 pregnant women. With the progress of pregnancy, the proportion of pregnant women with high normal blood pressure (BP) and the incidence of HDP increased gradually. The incidence of HDP increased with pregnancy age, body mass index, and BP of pregnant women during first trimester. What are the implications for public health practice? To reduce the incidence of HDP effectively, we should pay more attention to older women who plan to become pregnant, measures should be taken to control BP and weight in pre-pregnancy.

Association of Nighttime Sleep Duration with Depressive Symptoms and Its Interaction with Regular Physical Activity among Chinese Adolescent Girls.

Depression has become a major mental health concern among adolescents globally, and the relationship between depressive symptoms and nighttime sleep duration among adolescent girls remains unclear. This study aimed to examine the association between nighttime sleep duration and depressive symptoms among Chinese adolescent girls. This cross-sectional study, conducted in 2018, included 4952 girls aged 10-19 years from the eastern, central, and western regions of China. Depressive symptoms were assessed by the Patient Health Questionnaire-9, and categorized into depressive symptoms and non-depressive symptoms. Logistic regression models were used to estimate the odds ratios (ORs) of depressive symptoms. After adjustment for covariates, adolescent girls with a nighttime sleep duration of <7 h/night (OR = 2.28, 95% CI: 1.76-2.95) and 7 h/night (OR = 1.82, 95% CI: 1.48-2.24) were associated with increased risk of depressive symptoms, compared to those with a sleep duration of 8 h/night. An interaction between nighttime sleep duration and regular physical activity on the risk of depressive symptoms was observed (p for interaction = 0.036). Among both girls with and without regular physical activity, a sleep duration of <7 h/night was associated with increased odds of depressive symptoms, and the magnitude of the ORs among girls with regular physical activity was lower than those without regular physical activity. This study found a significant association of short nighttime sleep duration with increased risk of depressive symptoms, and demonstrates the importance of maintaining adequate nighttime sleep duration and ensuring regular physical activity in improving depressive symptoms among adolescent girls.