A new study ties the odds of conception to the advantages of the neighborhood a woman lives in.
In a cohort of more than 6,000 women who were trying to get pregnant without fertility treatments, the probability of conception was reduced 21%-23% per menstrual cycle when comparing the most disadvantaged neighborhoods with the least disadvantaged.
“When disadvantaged neighborhood status was categorized within each state (as opposed to nationally), the results were slightly larger in magnitude,” wrote authors of the study published online in JAMA Network Open.
Among 6,356 participants, 3,725 pregnancies were observed for 27,427 menstrual cycles of follow-up. Average age was 30, and most participants were non-Hispanic White (5,297 [83.3%]) and had not previously given birth (4,179 [65.7%]).
When the researchers compared the top and bottom deciles of disadvantaged neighborhood status, adjusted fecundability ratios (the per-cycle probability of conception) were 0.79 (95% confidence interval [CI], 0.66-0.96) for national-level area deprivation index (ADI) rankings and 0.77 (95% CI, 0.65-0.92) for within-state ADI rankings. ADI score includes population indicators related to educational attainment, housing, employment, and poverty.
“These findings suggest that investments in disadvantaged neighborhoods may yield positive cobenefits for fertility,” the authors wrote.
The researchers used the Pregnancy Study Online, for which baseline data were collected from women in the United States from June 19, 2013, through April 12, 2019.
In the United States, 10%-15% of reproductive-aged couples experience infertility, defined as the inability to conceive after a year of unprotected intercourse.
Reason behind the numbers unclear
Mark Hornstein, MD, director in the reproductive endocrinology division of Brigham and Women’s Hospital and professor at Harvard Medical School, both in Boston, said in an interview that this study gives the “what” but the “why” is harder to pinpoint.
What is not known, he said, is what kind of access the women had to fertility counseling or treatment.
The association between fertility and neighborhood advantage status is very plausible given the well-established links between disadvantaged regions and poorer health outcomes, he said, adding that the authors make a good case for their conclusions in the paper.
The authors ruled out many potential confounders, such as age of the women, reproductive history, multivitamin use, education level, household income, and frequency of intercourse, and still there was a difference between disadvantaged and advantaged neighborhoods, he noted.
Dr. Hornstein said his own research team has found that lack of knowledge about insurance coverage regarding infertility services may keep women from seeking the services.
“One of the things I worry about it access,” he said. “[The study authors] didn’t really look at that. They just looked at what the chances were that they got pregnant. But they didn’t say how many of those women had a workup, an evaluation, for why they were having difficulty, if they were, or had treatment. So I don’t know if some or all or none of that difference that they saw from the highest neighborhood health score to the most disadvantaged – if that was from inherent problems in the area, access to the best health care, or some combination.”