According to the authors, investments in deprived areas could improve fertility.
According to a recent Oregon State University study, residents of socioeconomically deprived neighborhoods are 20% less likely to get pregnant during any given menstrual cycle than residents of neighborhoods with greater resources.
The research assessed “fecundability,” or the monthly likelihood of becoming pregnant, among couples seeking to conceive without the use of fertility treatments.
A measure of the socioeconomic resources of a neighborhood, the “area deprivation index” score was used by researchers to compare neighborhoods. They discovered that even within a relatively affluent, highly educated study population, those residing in more deprived areas had lower fecundability rates than those living in neighborhoods with more opportunities.
“The world of fertility research is beginning to examine factors associated with the built environment. There are dozens of studies looking at how your neighborhood environment is associated with adverse birth outcomes, but the pre-conception period is heavily under-studied from a structural standpoint,” said lead author Mary Willis, a postdoctoral scholar in OSU’s College of Public Health and Human Sciences. “Turns out, before you’re even conceived, there may be things affecting your health.”
In the last ten years, public health research has highlighted the importance of social determinants of health and the notion that the ZIP code is the best indicator of overall life expectancy based on variables including income, education level, access to good water, employment rates, and health care.
“But the concept that your neighborhood affects your fertility hasn’t been studied in depth,” Willis said. “In addition, the world of infertility research is largely focused on individual factors, so when I came into this study as an environmental epidemiologist, I was thinking we should look at it as a structural problem.”
The study leveraged data from an ongoing study by Boston University, the Pregnancy Study Online (PRESTO). Researchers analyzed a cohort of 6,356 individuals ranging from 21 to 45 years old, attempting to conceive without the use of fertility treatment, in data compiled from 2013 through 2019.
Study participants filled out online surveys every eight weeks for up to 12 months, answering questions about menstrual cycle characteristics and pregnancy status. In the study time period, 3,725 pregnancies were documented.
Researchers compared participants across different area deprivation index rankings at both the national and within-state levels, which used socioeconomic indicators including educational attainment, housing, employment, and poverty.
They found that participants in the most-deprived neighborhoods based on the national rankings had a 19-21% reduction in fecundability compared with those in the least-deprived neighborhoods. Based on within-state rankings, the most-deprived neighborhoods saw a 23-25% reduction in fecundability compared with the least deprived areas.
The majority of people in the cohort were white, had completed a four-year college education, and earned more than $50,000 a year.
“The fact that we’re seeing the same results on the national and state level really shows that neighborhood deprivation can influence reproductive health, including fertility,” Willis said.
Approaching fertility research from a structural standpoint might help reduce or prevent infertility overall, she said, especially because fertility treatments are costly and usually only accessible to families with significant resources.
The study concludes that investments in deprived neighborhoods to address socioeconomic disparities may yield positive benefits for fertility.
Reference: “Association Between Neighborhood Disadvantage and Fertility Among Pregnancy Planners in the US” by Mary D. Willis, Ph.D., Olivia R. Orta, ScD, Collette Ncube, DrPH, Amelia K. Wesselink, Ph.D., Lan N. Đoàn, Ph.D., Kipruto Kirwa, Ph.D., Renée Boynton-Jarrett, MD, ScD, Elizabeth E. Hatch, Ph.D. and Lauren A. Wise, ScD, 30 June 20222, Environmental Health.