Association Between Neighborhood Disadvantage and Fertility Among Pregnancy Planners in the US

2022  Journal Article

Association Between Neighborhood Disadvantage and Fertility Among Pregnancy Planners in the US

Pub TLDR

This study examines the association between living in socioeconomically disadvantaged neighborhoods and fecundability among pregnancy planners in the US. The findings indicate that residence in such neighborhoods is linked to moderately decreased fecundability, suggesting that improving neighborhood conditions could positively impact fertility outcomes.

 

Highlights

Question

Is living in a disadvantaged neighborhood associated with decreased fertility?

Findings

In this cohort study of 6356 women attempting to conceive without the use of fertility treatment, the probability of conception was reduced 21% to 23% per menstrual cycle when comparing the highest with the lowest deciles of disadvantaged neighborhoods. When disadvantaged neighborhood status was categorized within each state (as opposed to nationally), the results were slightly larger in magnitude.

Meaning

These findings suggest that investments in disadvantaged neighborhoods may yield positive cobenefits for fertility.

Abstract

Importance

Decades of inequitable policies in the US have yielded disparities in neighborhood quality, and some studies show that living in a socioeconomically disadvantaged neighborhood is associated with worse health outcomes, including reproductive health outcomes. However, no US studies to date have directly examined the association between residence in disadvantaged neighborhoods and fertility.

Objective

To examine the association between residence in disadvantaged neighborhoods and fecundability, a sensitive marker of fertility with many health implications.

Design, Setting, and Participants

This prospective preconception cohort study used the Pregnancy Study Online, for which baseline data were collected from June 19, 2013, through April 12, 2019. The study included 6356 participants who identified as female, were 21 to 45 years of age, were attempting conception without fertility treatment, and provided a valid residential address in the contiguous US at enrollment.

Exposures

A standardized area deprivation index (ADI) derived at the census block group level applied to each residential address.

Main Outcomes and Measures

Fecundability, the per-cycle probability of conception, via questionnaires that were completed every 8 weeks for 12 months, until conception or a censoring event. Proportional probabilities models were used to estimate fecundability ratios and 95% CIs for associations between ADI and fecundability. Restricted cubic splines were also implemented to examine nonlinearity. Models were adjusted for demographic characteristics and factors associated with fertility. The study’s a priori hypothesis was that higher levels of neighborhood disadvantage would be associated with decreased fecundability.

Results

Among 6356 participants, 3725 pregnancies were observed for 27 427 menstrual cycles of follow-up. The mean (SD) baseline age was 30.0 (4.1) years, and most participants were non-Hispanic White (5297 [83.3%]) and nulliparous (4179 [65.7%]). Comparing the top and bottom deciles of disadvantaged neighborhood status, adjusted fecundability ratios were 0.79 (95% CI, 0.66-0.96) for national-level ADI rankings and 0.77 (95% CI, 0.65-0.92) for within-state ADI rankings. Restricted cubic splines showed some evidence of nonlinearity in the association. Associations were slightly stronger among participants with lower annual incomes (<$50 000).

Conclusions and Relevance

In this cohort study, residence in a socioeconomically disadvantaged neighborhood was associated with moderately decreased fecundability. If confirmed in other studies, these results suggest that investments to reduce disadvantaged neighborhood status may yield positive cobenefits for fertility.

Willis, M.D., Orta, O.R., Ncube, C.N., Wesselink, A.K., Đoàn, L.N., Kirwa, K., Boynton-Jarrett, R., Hatch, E.E., Wise, L.A.(2022)Association Between Neighborhood Disadvantage and Fertility Among Pregnancy Planners in the USJAMA Network Open5
 
Publication FAQ

FAQ: Neighborhood Disadvantage and Fertility

What is the main finding of the study?

This prospective cohort study found that women residing in socioeconomically disadvantaged neighborhoods had a 21% to 23% lower probability of conceiving each menstrual cycle compared to women living in the least disadvantaged neighborhoods. This association remained significant even after adjusting for factors like age, income, education, and lifestyle.

How was neighborhood disadvantage measured?

The researchers used the Area Deprivation Index (ADI), a standardized metric that assesses socioeconomic disadvantage at the census block group level. The ADI incorporates factors such as education level, employment status, income, and housing quality. Higher ADI scores indicate greater neighborhood disadvantage.

What is fecundability and why is it important?

Fecundability refers to the probability of a couple conceiving within a single menstrual cycle. It's a key indicator of fertility and offers insights into reproductive health. Reduced fecundability suggests a lower chance of achieving pregnancy within a desired timeframe.

What are the possible explanations for this association?

While the study doesn't definitively prove causation, several pathways might explain the link between disadvantaged neighborhoods and reduced fecundability. These include:

  • Chronic Stress: Residents of disadvantaged neighborhoods often experience higher levels of stress due to factors like financial strain, lack of access to resources, and exposure to crime. Chronic stress can disrupt hormonal balance and negatively impact reproductive function.
  • Environmental Factors: Disadvantaged neighborhoods are more likely to have higher levels of air and water pollution, along with limited access to green spaces. These environmental factors have been linked to reduced fertility.
  • Health Disparities: Individuals in disadvantaged neighborhoods often face barriers to healthcare access and quality, leading to disparities in overall health status, which can in turn affect reproductive health.

What are the implications of these findings for public health?

The study highlights the potential impact of social determinants of health on reproductive outcomes. It suggests that public health interventions aimed at improving neighborhood conditions and reducing socioeconomic disparities could have positive co-benefits for fertility and reproductive health equity.

Did the study consider individual socioeconomic factors?

Yes, the researchers analyzed the influence of factors like income, education, and race/ethnicity. They found that adjusting for these individual factors partially attenuated the association between ADI and fecundability, suggesting they may act as mediators in the relationship.

What are the limitations of the study?

The study has some limitations. The researchers relied on self-reported data for some variables, potentially leading to measurement error. The study population consisted primarily of pregnancy planners with higher socioeconomic status than the general US population, limiting generalizability of the findings. Additionally, while the study highlights a correlation, it cannot definitively establish a causal relationship between neighborhood disadvantage and reduced fecundability.

What future research is needed in this area?

Further research is necessary to confirm these findings in more diverse populations and explore the specific mechanisms linking neighborhood disadvantage to reduced fertility. Studies examining the effectiveness of interventions aimed at improving neighborhood conditions on reproductive health outcomes are also needed.