Spatial and temporal patterns in preterm birth in the United States

Advancing geospatial preconception health research in primary care through medical informatics and artificial intelligence

Established life course approaches suggest that health status in adulthood can be influenced by events that occurred during the prenatal developmental period. Yet, interventions such as diet and lifestyle changes performed during pregnancy have had a small impact on both maternal and offspring health outcomes. Currently, there is a growing body of literature that highlights the importance of maternal health before conception (months or years before pregnancy occurs) for the future health of offspring. While some studies have explored factors such as maternal body composition, nutrition, and lifestyle in this area, location-based environmental and socioeconomic exposures before conception may also contribute to future offspring health. In this line, the study of a patient's geographic history presents a promising avenue. To foster research in this direction, the integration of geospatial health, medical informatics and artificial intelligence techniques offers great potential. Importantly, novel sources of big health data sets such as electronic health records registered at the primary care level provide a unique framework due to its inherent longitudinal nature. Nonetheless, a number of privacy, ethical, and technical challenges need to be overcome for this kind of longitudinal analysis to mature and succeed. In the long-term, we support the vision of incorporating a patient's geographic history into her clinical history to equip clinicians with useful contextual information to explore.

US County-Level Variation in Preterm Birth Rates, 2007-2019

Importance

Preterm birth is a leading cause of preventable neonatal morbidity and mortality. Preterm birth rates at the national level may mask important geographic variation in rates and trends at the county level.

Objective

To estimate age-standardized preterm birth rates by US county from 2007 to 2019.

Design, Setting, and Participants

This serial cross-sectional study used data from the National Center for Health Statistics composed of all live births in the US between 2007 and 2019. Data analyses were performed between March 22, 2022, and September 29, 2022.

Main Outcomes and Measures

Age-standardized preterm birth (<37 weeks' gestation) and secondarily early preterm birth (<34 weeks' gestation) rates by county and year calculated with a validated small area estimation model (hierarchical bayesian spatiotemporal model) and percent change in preterm birth rates using log-linear regression models.

Results

Between 2007 and 2019, there were 51 044 482 live births in 2383 counties. In 2007, the national age-standardized preterm birth rate was 12.6 (95% CI, 12.6-12.7) per 100 live births. Preterm birth rates varied significantly among counties, with an absolute difference between the 90th and 10th percentile counties of 6.4 (95% CI, 6.2-6.7). The gap between the highest and lowest counties for preterm births was 20.7 per 100 live births in 2007. Several counties in the Southeast consistently had the highest preterm birth rates compared with counties in California and New England, which had the lowest preterm birth rates. Although there was no statistically significant change in preterm birth rates between 2007 and 2019 at the national level (percent change, -5.0%; 95% CI, -10.7% to 0.9%), increases occurred in 15.4% (95% CI, 14.1%-16.9%) of counties. The absolute and relative geographic inequalities were similar across all maternal age groups. Higher quartile of the Social Vulnerability Index was associated with higher preterm birth rates (quartile 4 vs quartile 1 risk ratio, 1.34; 95% CI, 1.31-1.36), which persisted across the study period. Similar patterns were observed for early preterm birth rates.

Conclusions and Relevance

In this serial cross-sectional study of county-level preterm and early preterm birth rates, substantial geographic disparities were observed, which were associated with place-based social disadvantage. Stability in aggregated rates of preterm birth at the national level masked increases in nearly 1 in 6 counties between 2007 and 2019.

Association of maternal education, neighborhood deprivation, and racial segregation with gestational age at birth by maternal race/ethnicity and United States Census region in the ECHO cohorts

Background

In the United States, disparities in gestational age at birth by maternal race, ethnicity, and geography are theorized to be related, in part, to differences in individual- and neighborhood-level socioeconomic status (SES). Yet, few studies have examined their combined effects or whether associations vary by maternal race and ethnicity and United States Census region.

Methods

We assembled data from 34 cohorts in the Environmental influences on Child Health Outcomes (ECHO) program representing 10,304 participants who delivered a liveborn, singleton infant from 2000 through 2019. We investigated the combined associations of maternal education level, neighborhood deprivation index (NDI), and Index of Concentration at the Extremes for racial residential segregation (ICERace) on gestational weeks at birth using linear regression and on gestational age at birth categories (preterm, early term, post-late term relative to full term) using multinomial logistic regression.

Results

After adjustment for NDI and ICERace, gestational weeks at birth was significantly lower among those with a high school diploma or less (-0.31 weeks, 95% CI: -0.44, -0.18), and some college (-0.30 weeks, 95% CI: -0.42, -0.18) relative to a master's degree or higher. Those with a high school diploma or less also had an increased odds of preterm (aOR 1.59, 95% CI: 1.20, 2.10) and early term birth (aOR 1.26, 95% CI: 1.05, 1.51). In adjusted models, NDI quartile and ICERace quartile were not associated with gestational weeks at birth. However, higher NDI quartile (most deprived) associated with an increased odds of early term and late term birth, and lower ICERace quartile (least racially privileged) associated with a decreased odds of late or post-term birth. When stratifying by region, gestational weeks at birth was lower among those with a high school education or less and some college only among those living in the Northeast or Midwest. When stratifying by race and ethnicity, gestational weeks at birth was lower among those with a high school education or less only for the non-Hispanic White category.

Conclusion

In this study, maternal education was consistently associated with shorter duration of pregnancy and increased odds of preterm birth, including in models adjusted for NDI and ICERace.

The association between care management and neonatal outcomes: the role of a Medicaid-managed pregnancy medical home in North Carolina

BACKGROUND

Preterm birth is a significant clinical and public health issue in the United States. Rates of preterm birth have remained unchanged, and racial disparities persist. Although a causal pathway has not yet been defined, it is likely that a multitude of clinical and social risk factors contribute to a pregnant person's risk. State-based public health and provider programmatic partnerships have the potential to improve care during pregnancy and reduce complications, such as preterm birth. In North Carolina, a state-based Medicaid-managed Pregnancy Medical Home Program screens pregnant individuals for psychosocial and medical risk factors and utilizes community-based care management, to offer support to those at highest risk.

OBJECTIVE

This study aimed to examine the association between care-management and birth outcomes (low birthweight and preterm birth rates) among high-risk non-Hispanic White and Black pregnant people enrolled in the North Carolina Pregnancy Medical Home.

STUDY DESIGN

This was a quasi-experimental study of people in the Medicaid-managed North Carolina Pregnancy Medical Home who had singleton pregnancies and who enrolled in the program between January 2016 and December 2017. Black and White pregnant people were included in the analysis if they had singleton pregnancies, were enrolled in the Pregnancy Medical Home, and for whom there were data regarding care management involvement. Preterm birth and low birthweight were chosen as the outcomes of interest. Two different methodologies were used to test the effect of care management on outcomes: Method 1 evaluated the effect of intensive care management (≥5 face-to-face visits from a care manager) and Method 2 evaluated the effect of the implementation of a specific risk-stratification system. Chi-squared and multivariate logistic regressions were performed as appropriate.

RESULTS

From January 1, 2016 to December 31, 2017, a total of 3564 singleton pregnancies occurred among non-Hispanic Black and White pregnant Medicaid beneficiaries, who were a part of the Pregnancy Medical Home in North Carolina. White pregnant people comprised 57% and Black pregnant people comprised 43% of the sample. In the Method 1 analysis, intensive care management was significantly associated with reductions in preterm birth and low birthweight among Black and White pregnant people whereas in the Method 2 analysis, the implementation of a risk-stratification score only resulted in a significant reduction among Black pregnant people. In multivariable logistic modeling, race, number of prenatal visits, and intensive care management were all significantly associated with the outcomes of interest.

CONCLUSION

Care management is associated with reductions in preterm birth and low birthweight in the Medicaid-managed Pregnancy Medical Home in North Carolina. This study contributes to a growing body of literature on the role of state-based initiatives in reducing perinatal morbidity. These results are significant as it demonstrates the importance of care coordination and management, in identifying and providing resources for high-risk pregnant people. In the United States, where pregnancy-related outcomes are poor, programs that address the multitude of economic, social, and clinical complexities are becoming increasingly crucial and necessary.

Differences in Rates of Low Birth Weight among Prefectures in Japan: An Ecological Study Using Government Statistics Data

The differences in the rates and trends of the overall low birth weight and term low birth weight in recent years are unknown for the Japanese prefectures. In this ecological study, we revealed the rates for each prefecture and investigated the factors affecting the regional differences in these outcomes. Aggregated vital statistics data from 2007 to 2019 were obtained from the Ministry of Health, Labour, and Welfare in Japan. The association between the outcomes and the variables, including the infants’ birth characteristics, medical characteristics, and socioeconomic characteristics of the prefectures, were analyzed. An analysis of repeated-measures data was conducted using the data from 2013 and 2018 for each prefecture. The trend for the rates of overall low birth weight and term low birth weight over the years differed among the prefectures. Moreover, the proportions of multiple births and lean (body mass index <18.5 kg/m2) and obese (body mass index ≥25.0 kg/m2) women had a statistically significant positive association with both the overall low birth weight rate and the term low birth weight rate among the prefectures. It was suggested that to resolve the difference in these outcomes among the prefectures, being obese or underweight needs to be addressed in mothers.

Racial and geographic variation in effects of maternal education and neighborhood-level measures of socioeconomic status on gestational age at birth: Findings from the ECHO cohorts

Preterm birth occurs at excessively high and disparate rates in the United States. In 2016, the National Institutes of Health (NIH) launched the Environmental influences on Child Health Outcomes (ECHO) program to investigate the influence of early life exposures on child health. Extant data from the ECHO cohorts provides the opportunity to examine racial and geographic variation in effects of individual- and neighborhood-level markers of socioeconomic status (SES) on gestational age at birth. The objective of this study was to examine the association between individual-level (maternal education) and neighborhood-level markers of SES and gestational age at birth, stratifying by maternal race/ethnicity, and whether any such associations are modified by US geographic region. Twenty-six ECHO cohorts representing 25,526 mother-infant pairs contributed to this disseminated meta-analysis that investigated the effect of maternal prenatal level of education (high school diploma, GED, or less; some college, associate's degree, vocational or technical training [reference category]; bachelor's degree, graduate school, or professional degree) and neighborhood-level markers of SES (census tract [CT] urbanicity, percentage of black population in CT, percentage of population below the federal poverty level in CT) on gestational age at birth (categorized as preterm, early term, full term [the reference category], late, and post term) according to maternal race/ethnicity and US region. Multinomial logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CIs). Cohort-specific results were meta-analyzed using a random effects model. For women overall, a bachelor's degree or above, compared with some college, was associated with a significantly decreased odds of preterm birth (aOR 0.72; 95% CI: 0.61-0.86), whereas a high school education or less was associated with an increased odds of early term birth (aOR 1.10, 95% CI: 1.00-1.21). When stratifying by maternal race/ethnicity, there were no significant associations between maternal education and gestational age at birth among women of racial/ethnic groups other than non-Hispanic white. Among non-Hispanic white women, a bachelor's degree or above was likewise associated with a significantly decreased odds of preterm birth (aOR 0.74 (95% CI: 0.58, 0.94) as well as a decreased odds of early term birth (aOR 0.84 (95% CI: 0.74, 0.95). The association between maternal education and gestational age at birth varied according to US region, with higher levels of maternal education associated with a significantly decreased odds of preterm birth in the Midwest and South but not in the Northeast and West. Non-Hispanic white women residing in rural compared to urban CTs had an increased odds of preterm birth; the ability to detect associations between neighborhood-level measures of SES and gestational age for other race/ethnic groups was limited due to small sample sizes within select strata. Interventions that promote higher educational attainment among women of reproductive age could contribute to a reduction in preterm birth, particularly in the US South and Midwest. Further individual-level analyses engaging a diverse set of cohorts are needed to disentangle the complex interrelationships among maternal education, neighborhood-level factors, exposures across the life course, and gestational age at birth outcomes by maternal race/ethnicity and US geography.

Geographic Hotspots for Low Birthweight: An Analysis of Counties With Persistently High Rates

This study evaluated persistency in county-level rates of low birthweight outcomes to identify “hotspot counties” and their associated area-level characteristics. Administrative data from the National Center for Health Statistics Birth Data Files, years 2011 to 2016 were used to calculate annual county-level rates of low birthweight. Counties ranking in the worst quintile (Q5) for ≥3 years with a neighboring county in the worst quintile were identified as hotspot counties. Multivariate logistic regression was used to associate county-level characteristics with hotspot designation. Adverse birth outcomes were persistent in poor performing counties, with 52% of counties in Q5 for low birthweight in 2011 remaining in Q5 in 2016. The rate of low birthweight among low birthweight hotspot counties (n = 495) was 1.6 times the rate of low birthweight among non-hotspot counties (9.3% vs 5.8%). The rate of very low birthweight among very low birthweight hotspot counties (n = 387) was twice as high compared to non-hotspot counties (1.8% vs 0.9%). A one standard deviation (6.5%) increase in the percentage of adults with at least a high school degree decreased the probability of low birthweight hotspot designation by 1.7 percentage points (P = .006). A one standard deviation (20%) increase in the percentage of the population that was of minority race/ethnicity increased hotspot designation for low birthweight by 5.7 percentage points (P < .001). Given the association between low birthweight and chronic conditions, hotspot counties should be a focus for policy makers in order to improve health equity across the life course.

An overview of GeoAI applications in health and healthcare

The moulding together of artificial intelligence (AI) and the geographic/geographic information systems (GIS) dimension creates GeoAI. There is an emerging role for GeoAI in health and healthcare, as location is an integral part of both population and individual health. This article provides an overview of GeoAI technologies (methods, tools and software), and their current and potential applications in several disciplines within public health, precision medicine, and Internet of Things-powered smart healthy cities. The potential challenges currently facing GeoAI research and applications in health and healthcare are also briefly discussed.

Features of serial cranial ultrasound detected neuropathology in very preterm infants

BACKGROUND

The purpose of this study was to identify the pattern and factors associated with changes in cranial ultrasound (CUS) -detected findings in infants born at or less than 28 weeks of gestation.

METHODS

We compared readings of CUS performed at the end of the first week of life and at 4-5 weeks of age. Alteration of CUS findings was classified as: (i) unchanged, if no deviation was detected (Group 1); (ii) worsening, if there were new findings (Group 2); and (iii) improvement, if there was normalization or reduction in severity (Group 3). Descriptive statistics, multivariate controlled logistic regression, and kappa (k) statistics with 95% Confidence Interval (95% CI) were reported.

RESULTS

Among 510 studied infants, 82.3% (95% CI 78.8-85.4) were in Group 1, 10.0% (95% CI 7.7-12.9) in Group 2, and 7.7% (95% CI 5.7-10.3) in Group 3. Overall agreement between the two scans was moderate (k 0.62; 95% CI 0.55-0.69). Worsening of CUS findings was associated with neonatal morbidities independently from gestational age and birth weight. The probability for worsening of CUS findings was higher in infants with an initial diagnosis of intraventricular hemorrhage (IVH) grade 2, than in those reported as no pathology/IVH grade 1 (Odds Ratio 5.79; 95% CI 2.42-13.91) or IVH grade 3-4 (Odds Ratio 3.81; 95% CI 1.10-13.21).

CONCLUSIONS

In very preterm born infants, the initial CUS findings in combination with neonatal morbidities can help predict the brain lesions that are seen at the end of the first month of life and could be useful in their clinical management.

Cervical pathways for racial disparities in preterm births: the Preterm Prediction Study

Purpose: Racial disparities in preterm birth have been long recognized, but the social and biological mechanisms for these differences are unclear. Our analysis had three goals: (1) to determine the relation between race and other social risk factors and cervical structure; (2) to determine whether social factors mediate the relation between race and cervical structure; and (3) to determine whether racial disparities in preterm birth (PTB) are mediated through changes in cervical structure observed earlier in pregnancy. Materials and methods: Data from the Maternal Fetal Medicine Unit network Preterm Prediction Study were used to examine the relation between race and other social factors and cervical properties throughout pregnancy in 2920 black and white women. Outcomes included cervical length and dilation; cervical score (cervical length-internal dilation); and whether membranes protruded at 22-24 and 26-29 weeks. Race, education, income, insurance type, and marital status were examined as predictors of the outcomes using linear and logistic regression, adjusting for age, BMI, parity, and smoking. Mediation analysis was used to examine whether (a) any social factors explained racial differences in cervical properties, and (b) whether cervical properties mediated racial differences in risk for preterm birth. Results: Shorter cervical length, especially at a subject's first visit, was associated with black race (adjusted beta -1.56 mm, p < .01) and lower income (adjusted beta -1.48, p =.05). External dilation was not associated with social factors, while internal dilation was associated with black race and lower education. Black race and marital status were associated with lower cervical score. There was no evidence of mediation of the racial effect on cervical properties by any social factor. Shorter cervical length, dilation, and score were all associated with preterm birth (p < .01). Mediation analysis indicated that each of these mediated the effect of race, but explained a small proportion of the total effect (15-25%). Conclusions: Race, and, to a lesser extent, other social factors are correlated with adverse cervical properties. This pathway could explain a proportion of the racial disparity in preterm birth.

Evaluation of a Multilevel Intervention to Reduce Preterm Birth Among Black Women in Newark, New Jersey: A Controlled Interrupted Time Series Analysis

Objective To evaluate the effectiveness of a multilevel intervention, Healthy Babies are Worth the Wait (HBWW), in reducing preterm birth (PTB) and very preterm birth (VPTB) among black women in Newark, NJ. Methods HBWW is a program linking the local March of Dimes office, providers, community-based organizations, and public health institutions to increase uptake of evidence based preterm birth interventions. We used birth certificate data before (2009-2011) and after (2012-2015) the introduction of HBWW in Newark. We estimated differences in PTB and VPTB between these periods among black women in Newark and compared them to rate differences among black women in the rest of NJ (difference-in-differences). We used interrupted time series analysis (ITSA) to examine declines in PTB and VPTB following the introduction of HBWW controlling for secular trends. All models adjusted for maternal age, education and parity. Results PTB declined in Newark 1.1 case per 100 (95% confidence interval (CI) - 2.3, 0) and in the rest of NJ 0.5 case per 100 (- 1.4, 0.4) (difference-in-differences = 0.6 fewer cases per 100 in Newark, 95% CI - 1.6, 0.3). VPTB declined in both Newark (- 0.6 cases per 100, 95% CI - 1.0, 0) and the rest of NJ (- 0.2 cases per 100, 95% CI - 0, 0.3) (difference-in-differences = 0.4 fewer cases per 100 in Newark, 95% CI - 0.9, 0). However, using ITSA the downward VPTB trend in Newark was not different from the rest of NJ or pre-intervention trends. Conclusions for Practice Our study supports the importance of critically evaluating and advancing complex interventions to reduce PTB among black women.

Mechanistic Differences Leading to Infectious and Sterile Inflammation

Inflammation is a physiologic component of pregnancy and parturition. Overwhelming intrauterine inflammatory load promotes quiescent feto-maternal tissues into a contractile phenotype. Like inflammation, oxidative stress is an inevitable component of both pregnancy and parturition. Pathologic activation of host innate immune response to adverse pregnancy conditions can lead to premature activation of inflammatory and oxidative stress. Inflammation and oxidative stress markers seen with both sterile and infectious inflammation are often similar; therefore, it is difficult to understand causality of conditions like spontaneous preterm birth. This review demonstrates potential mechanistic pathways of activation of sterile and infectious inflammation. We demonstrate the activation of two unique pathways of inflammation by factors that are well-documented proxies for oxidative stress (cigarette smoke extract) and infection (lipopolysaccharide). Sterile inflammation seen after exposure to an oxidative stress inducer is due to cellular elemental damage resulting in p38 mitogen-activated protein kinase (MAPK) induced cellular senescence. Infectious inflammation is through activation of transcription factor NF-κB and independent of oxidative stress-associated damages and p38 MAPK-induced senescence. Understanding the differences in the inflammatory pathway activation by various risk factors is important to design better screening, diagnostic and intervention strategies to reduce the risks of adverse pregnancy outcomes.

Using Geographic Information Science to Explore Associations between Air Pollution, Environmental Amenities, and Preterm Births

The study uses geographic information science (GIS) and statistics to find out if there are statistical differences between full term and preterm births to non-Hispanic white, non-Hispanic Black, and Hispanic mothers in their exposure to air pollution and access to environmental amenities (green space and vendors of healthy food) in the second largest city in New England, Worcester, Massachusetts. Proximity to a Toxic Release Inventory site has a statistically significant effect on preterm birth regardless of race. The air-pollution hazard score from the Risk Screening Environmental Indicators Model is also a statistically significant factor when preterm births are categorized into three groups based on the degree of prematurity. Proximity to green space and to a healthy food vendor did not have an effect on preterm births. The study also used cluster analysis and found statistically significant spatial clusters of high preterm birth volume for non-Hispanic white, non-Hispanic Black, and Hispanic mothers.