Income inequality and pregnancy spacing

Obstetric Anal Sphincter Injury: Interpregnancy Interval and Route of Subsequent Delivery

IMPORTANCE

Knowledge on the interpregnancy interval (IPI) among women with an obstetric anal sphincter injury (OASI) is both limited and not well understood.

OBJECTIVES

The objectives of this study were to describe the IPI among women with OASI and to compare women with OASI based on the route of subsequent obstetric delivery and OASI recurrence.

STUDY DESIGN

This was a retrospective single-cohort study of women who had an OASI between 2013 and 2015 at a tertiary academic medical center. Demographics, obstetric delivery data, postpartum sequelae, and subsequent pregnancy delivery data from 2013 to 2021 were collected. The IPI was defined as the time from date of first vaginal delivery to date of conception of the subsequent pregnancy. Women without a subsequent pregnancy were censored at the date of last contact. The IPI was evaluated using a survival analysis (Kaplan-Meier estimator).

RESULTS

A total of 287 women experienced an OASI, and subsequent pregnancy occurred for 178 (62.0%) women. The median IPI was 26.4 months (95% confidence interval: 23.7-29.9) for women with a prior OASI. Of the 97 women who did not have a subsequent pregnancy documented during the study, the median follow-up was 64.0 months (interquartile range: 5.7-80.0). Subsequent delivery route data were available for 171 women; of those, 127 (74.3%) experienced a subsequent vaginal delivery and 44 (25.7%) experienced a cesarean delivery. Of the 127 women who experienced a subsequent vaginal delivery, 3 (2.4%) experienced a recurrent OASI.

CONCLUSION

The IPI among women with OASI is similar to the IPI for all women in Ohio and in the United States.

Short Interpregnancy Intervals Among Women Experiencing Homelessness in Colorado

Importance

Short interpregnancy intervals (SIPIs) are associated with increased risk of adverse maternal and neonatal outcomes. Disparities exist across socioeconomic status, but there is little information on SIPIs among women experiencing homelessness.

Objective

To investigate (1) differences in rates and characteristics of SIPIs between women experiencing homelessness and domiciled women, (2) whether the association of homelessness with SIPIs differs across races and ethnicities, and (3) whether the association between SIPIs of less than 6 months (very short interpregnancy interval [VSIPIs]) and maternal and neonatal outcomes differs between participant groups.

Design, Setting, and Participants

This cohort study used a Colorado statewide database linking the Colorado All Payer Claims Database, Homeless Management Information System, death records, and infant birth records. Participants included all women who gave birth between January 1, 2016, and December 31, 2021. Data were analyzed from September 1, 2022, to May 10, 2023.

Exposures

Homelessness and race and ethnicity.

Main Outcomes and Measures

The primary outcome consisted of SIPI, a binary variable indicating whether the interval between delivery and conception of the subsequent pregnancy was shorter than 18 months. The association of VSIPI with maternal and neonatal outcomes was also tested.

Results

A total of 77 494 women (mean [SD] age, 30.7 [5.3] years) were included in the analyses, of whom 636 (0.8%) were women experiencing homelessness. The mean (SD) age was 29.5 (5.4) years for women experiencing homelessness and 30.7 (5.3) years for domiciled women. In terms of race and ethnicity, 39.3% were Hispanic, 7.3% were non-Hispanic Black, and 48.4% were non-Hispanic White. Associations between homelessness and higher odds of SIPI (adjusted odds ratio [AOR], 1.23 [95% CI, 1.04-1.46]) were found. Smaller associations between homelessness and SIPI were found among non-Hispanic Black (AOR, 0.59 [95% CI, 0.37-0.96]) and non-Hispanic White (AOR, 0.57 [95% CI, 0.39-0.84]) women compared with Hispanic women. A greater association of VSIPI with emergency department visits and low birth weight was found among women experiencing homelessness compared with domiciled women, although no significant differences were detected.

Conclusions and Relevance

In this cohort study of women who gave birth from 2016 to 2021, an association between homelessness and higher odds of SIPIs was found. These findings highlight the importance of conception management among women experiencing homelessness. Racial and ethnic disparities should be considered when designing interventions.

The confounder matrix: A tool to assess confounding bias in systematic reviews of observational studies of etiology

Systematic reviews and meta-analyses are essential for drawing conclusions regarding etiologic associations between exposures or interventions and health outcomes. Observational studies comprise a substantive source of the evidence base. One major threat to their validity is residual confounding, which may occur when component studies adjust for different sets of confounders, fail to control for important confounders, or have classification errors resulting in only partial control of measured confounders. We present the confounder matrix-an approach for defining and summarizing adequate confounding control in systematic reviews of observational studies and incorporating this assessment into meta-analyses. First, an expert group reaches consensus regarding the core confounders that should be controlled and the best available method for their measurement. Second, a matrix graphically depicts how each component study accounted for each confounder. Third, the assessment of control adequacy informs quantitative synthesis. We illustrate the approach with studies of the association between short interpregnancy intervals and preterm birth. Our findings suggest that uncontrolled confounding, notably by reproductive history and sociodemographics, resulted in exaggerated estimates. Moreover, no studies adequately controlled for all core confounders, so we suspect residual confounding is present, even among studies with better control. The confounder matrix serves as an extension of previously published methodological guidance for observational research synthesis, enabling transparent reporting of confounding control and directly informing meta-analysis so that conclusions are drawn from the best available evidence. Widespread application could raise awareness about gaps across a body of work and allow for more valid inference with respect to confounder control.

Obstetric Care Consensus No. 8: Interpregnancy Care

Interpregnancy care aims to maximize a woman's level of wellness not just in between pregnancies and during subsequent pregnancies, but also along her life course. Because the interpregnancy period is a continuum for overall health and wellness, all women of reproductive age who have been pregnant regardless of the outcome of their pregnancies (ie, miscarriage, abortion, preterm, full-term delivery), should receive interpregnancy care as a continuum from postpartum care. The initial components of interpregnancy care should include the components of postpartum care, such as reproductive life planning, screening for depression, vaccination, managing diabetes or hypertension if needed, education about future health, assisting the patient to develop a postpartum care team, and making plans for long-term medical care. In women with chronic medical conditions, interpregnancy care provides an opportunity to optimize health before a subsequent pregnancy. For women who will not have any future pregnancies, the period after pregnancy also affords an opportunity for secondary prevention and improvement of future health.

Interpregnancy Care

Interpregnancy care aims to maximize a woman's level of wellness not just in between pregnancies and during subsequent pregnancies, but also along her life course. Because the interpregnancy period is a continuum for overall health and wellness, all women of reproductive age who have been pregnant regardless of the outcome of their pregnancies (ie, miscarriage, abortion, preterm, full-term delivery), should receive interpregnancy care as a continuum from postpartum care. The initial components of interpregnancy care should include the components of postpartum care, such as reproductive life planning, screening for depression, vaccination, managing diabetes or hypertension if needed, education about future health, assisting the patient to develop a postpartum care team, and making plans for long-term medical care. In women with chronic medical conditions, interpregnancy care provides an opportunity to optimize health before a subsequent pregnancy. For women who will not have any future pregnancies, the period after pregnancy also affords an opportunity for secondary prevention and improvement of future health.

Community social capital on the timing of sexual debut and teen birth in Nicaragua: a multilevel approach

Background

Community attributes have been gradually recognized as critical determinants shaping sexual behaviors in young population; nevertheless, most of the published studies were conducted in high income countries. The study aims to examine the association between community social capital with the time to sexual onset and to first birth in Central America.

Methods

Building upon the 2011/12 Demographic and Health Survey conducted in Nicaragua, we identified a sample of 2766 community-dwelling female adolescents aged 15 to 19 years. Multilevel survival analyses were performed to estimate the risks linked with three domains of community social capital (i.e., norms, resource and social network).

Results

Higher prevalence of female sexual debut (norms) and higher proportion of secondary school or higher education (resource) in the community are associated with an earlier age of sexual debut by 47 % (p < 0.05) and 16 %, respectively (p < 0.001). Living in a community with a high proportion of females having a child increases the hazard of teen birth (p < 0.001) and resource is negatively associated with teen childbearing (p < 0.05). Residential stability and community religious composition (social network) were not linked with teen-onset sex and birth.

Conclusions

The norm and resource aspects of social capital appeared differentially associated with adolescent sexual and reproductive behaviors. Interventions aiming to tackle unfavorable sexual and reproductive outcomes in young people should be devised and implemented with integration of social process.

The role of geographic scale in testing the income inequality hypothesis as an explanation of health disparities

This study re-examined the role of geographic scale in measuring income inequality and testing the income inequality hypothesis (IIH) as an explanation of health disparities. We merged Behavioral Risk Factor Surveillance System (BRFSS) 2000 data with income inequality indices constructed at different geographic scales to test the association between income inequality and four different health indicators, i.e., self-assessed health status as a morbidity measure, vaccination against influenza as a measure of use of preventive healthcare, having any kind of health insurance as a measure of access, and obesity as a modifiable health risk factor measure. Multilevel models are used in our regression of the health indicators on measures of income inequalities and control variables. Our analysis suggests that because income inequality is a contextual variable, income inequalities measured at different geographic scales have different interpretations and relate to societal characteristics at different levels. Therefore, a rejection of the IIH at one level does not necessarily negate the possibility that income inequality affects health at another level. Assessment across a variety of scales is needed to have a comprehensive picture of the IIH in any given study. Empirical results also show that whether the IIH holds could depend on the sex group examined and the health indicator used, which implies different mechanisms of IIH exist for different sex groups and health indicators, in addition to the geographic scale. The role of geographic scale should be more rigorously considered in social determinants of health research.

Adolescent smoking risk increases with wider income gaps between rich and poor

Data from a state-wide survey of California middle and high school students (N=20,203) were used to assess whether county income inequality and poverty rates were associated with adolescent smoking. Greater county income inequality, but not poverty rates, was associated with higher established smoking risk (p=0.0019). The association was stronger in males than females, whites than other ethnic groups, and urban than rural settings. Neither county income inequality nor poverty rates were associated with experimental smoking. The findings suggest that it may be important to consider and address economic inequality in the prevention and control of adolescent tobacco use.

Income inequality and population health: A review and explanation of the evidence

Whether or not the scale of a society's income inequality is a determinant of population health is still regarded as a controversial issue. We decided to review the evidence and see if we could find a consistent interpretation of both the positive and negative findings. We identified 168 analyses in 155 papers reporting research findings on the association between income distribution and population health, and classified them according to how far their findings supported the hypothesis that greater income differences are associated with lower standards of population health. Analyses in which all adjusted associations between greater income equality and higher standards of population health were statistically significant and positive were classified as "wholly supportive"; if none were significant and positive they were classified as "unsupportive"; and if some but not all were significant and supportive they were classified as "partially supportive". Of those classified as either wholly supportive or unsupportive, a large majority (70 per cent) suggest that health is less good in societies where income differences are bigger. There were substantial differences in the proportion of supportive findings according to whether inequality was measured in large or small areas. We suggest that the studies of income inequality are more supportive in large areas because in that context income inequality serves as a measure of the scale of social stratification, or how hierarchical a society is. We suggest three explanations for the unsupportive findings reported by a minority of studies. First, many studies measured inequality in areas too small to reflect the scale of social class differences in a society; second, a number of studies controlled for factors which, rather than being genuine confounders, are likely either to mediate between class and health or to be other reflections of the scale of social stratification; and third, the international relationship was temporarily lost (in all but the youngest age groups) during the decade from the mid-1980s when income differences were widening particularly rapidly in a number of countries. We finish by discussing possible objections to our interpretation of the findings.

Predicting Time to Subsequent Pregnancy

OBJECTIVES

Women in poverty may benefit from avoiding closely spaced pregnancies. This study sought to identify predictive factors that could identify women at risk for closely spaced pregnancies.

METHODS

We studied 20,028 women receiving welfare (cash assistance) from Washington State. Using Cox proportional hazards methods, we estimated the effects of individual- and community-level variables on time from an index birth until a subsequent pregnancy (between June 1992 and December 1999). Prediction models developed in a random half of our data were validated in the other half. Receiver operator characteristic plots appropriate for proportional hazards models were calculated to compare the sensitivity and specificity of each model.

RESULTS

At 5 years of follow-up, the most predictive model contained just individual-level variables (age, education, race, marital status, number of prior pregnancies); the area under the receiver operator characteristic curve was 0.66 (.62-.69). The addition of community-level variables (percent in poverty, with a high school degree or higher, Black, Hispanic, in an urban area; female unemployment rate; income inequality) added little predictive ability. Differences were found between women with different individual- and community-level characteristics, but the results suggest that these factors are not strong predictors of pregnancy spacing.

CONCLUSIONS

Individual- and community-level characteristics are associated with interpregnancy intervals; however, we found little evidence that the selected variables predicted pregnancy interval in a useful manner.

Individual socio-economic status, community socio-economic status and stroke in New Zealand: a case control study

There is considerable debate about the association between individual socio-economic status, community socio-economic status and health. The current study examines individual data from a case-control study of stroke (n = 3489) conducted in Auckland, New Zealand. The study sought to identify whether individual socio-economic status (as measured by income from lifetime occupation) and community socio-economic status (measured in a number of ways) predicts the onset of stroke both independently and after controlling for individual risk factors (e.g., smoking, obesity and hypertension). Logistic regression results show that individual socio-economic status and all of the community socio-economic status measures predict the onset of stroke before controlling for individual risk factors. However, there is a high correlation between the various measures of community socio-economic status. Stepwise regression results suggest that average household income is the measure of community-level socio-economic status with the greatest predictive power. The results suggest that individual income and average household income are significant predictors of onset of stroke both independently and after controlling for behavioural and medical risk factors. Logistic regression analysis of the pathway suggests that individual income is a significant predictor of smoking and obesity, and that community socio-economic status is a significant predictor of heart disease, heavy drinking, diabetes, smoking and obesity.