Most cohort-based research for subfertility has been conducted in clinic-based cohorts, which may differ from population-based cohorts.
Methods
We retrospectively recruited parallel cohorts of subfertile women: one by sampling two specialty fertility clinics in Utah, and one by population-based sampling based on marriage and birth records. The index date (of first clinic visit or subfertility status) was between 2000 and 2009, and we linked the women recruited to subsequent birth certificate records through December 2010.
Results
We enrolled 459 women through clinic-based sampling and 501 women through population-based sampling. Clinic-based women were older, had higher annual household income and more likely to have had a most intensive treatment of intrauterine insemination (31%) or in vitro fertilisation (46%) than women from population recruitment (19% and 14% respectively). Conversely, they were less likely to have received no medical treatment (9%) compared to women from population recruitment (41%). For both types of sampling, prior to eligibility screening, non-responders were less likely to link to a live birth than responders: 51% vs. 58% for clinic-based, and 69% vs. 76% for the population-based with an index date in 2004.
Conclusions
Population-based sampling for subfertility cohort research identifies women who were more likely to have had less intensive treatment or no treatment. However, in both clinic-based and population-based sampling, women who have had a live birth are more likely to respond to retrospective recruitment.
subfertility cohort study methods, population-based fertility cohort, clinic-based infertility recruitment, Fertility Experiences Study design, retrospective subfertility outcomes, fertility treatment utilization patterns, subfertile women cohort comparison, infertility research methodology, population vs clinic fertility cohort, subfertility epidemiologic study design
PMID 27006293 27006293 DOI 10.1111/ppe.12291 10.1111/ppe.12291 Sanders et al. 2016, Sanders 2016
Cite this article
Stanford, J. B., Sanders, J. N., Simonsen, S. E., Hammoud, A., Gibson, M., & Smith, K. R. (2016). Methods for a Retrospective Population-based and Clinic-based Subfertility Cohort Study: the Fertility Experiences Study. Paediatric and perinatal epidemiology, 30(4), 397-407. https://doi.org/10.1111/ppe.12291
Stanford JB, Sanders JN, Simonsen SE, Hammoud A, Gibson M, Smith KR. Methods for a Retrospective Population-based and Clinic-based Subfertility Cohort Study: the Fertility Experiences Study. Paediatr Perinat Epidemiol. 2016;30(4):397-407. doi:10.1111/ppe.12291
Stanford, J. B., et al. "Methods for a Retrospective Population-based and Clinic-based Subfertility Cohort Study: the Fertility Experiences Study." Paediatric and perinatal epidemiology, vol. 30, no. 4, 2016, pp. 397-407.
Keywords
Adult, Birth Rate, Female, Fertilization in Vitro, Humans, Infertility/epidemiology/therapy, Male, Patient Selection, Preconception Care/methods, Pregnancy, Research Design, Retrospective Studies, Surveys and Questionnaires, Utah/epidemiology, Young Adult, Clinic-based, Population-based, Retrospective Cohort, Subfertility
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