Ethnic disparity in the use of ART treatment: a national register-based cross-sectional study among women in Denmark

STUDY QUESTION: Is ethnic background among 18- to 45-year-old women associated with initiating ART treatment in Denmark? SUMMARY ANSWER: Results indicate ethnic disparity in the use of ART treatment, with immigrants and their descendants having lower odds of initiating ART treatment compared to women with Danish origin. WHAT IS KNOWN ALREADY: The use of fertility treatment has increased over the past decades. Ethnic disparity exists in the use of health care, but there is limited knowledge about the association between migrant origin and use of fertility treatment. Previous studies have shown that women with lower socioeconomic position (SEP) have lower odds of initiating ART treatment compared to women with higher SEP. Immigrants and their descendants often have lower SEP compared to the general population (i.e. non-migrants or natives), but specific mechanisms might be at play when residing and navigating in a new country and healthcare system. STUDY DESIGN, SIZE, DURATION: This is a national, register-based study based on a sample of the Danish National ART-Couple (DANAC II) cohort, a full population cohort encompassing men and women registered with a Danish residence and with birth year between 1948 and 2006. Women initiating ART treatment (IVF or ICSI) aged 18-45 years were identified in the Danish IVF Register from 1994 to 2017. According to the time of ART treatment women were included in the study and randomly age-matched with 10 untreated women in the untreated background population. The study population consisted of 676 355 women. PARTICIPANTS/MATERIALS, SETTING, METHODS: The probability of initiating ART treatment was compared across ethnic groups and examined in logistic regression analyses. Migration status and country of origin were used as proxies for ethnic groups in separate analysis. Age was accounted for by matching, and additional factors of interest such as SEP measures were classified as potential mediators and thus not included in the main analyses. MAIN RESULTS AND THE ROLE OF CHANCE: The study population consisted of 526 507 (78%) women of Danish origin, 142 656 (21%) immigrants, and 7192 (1%) descendants of immigrants. Among women of Danish origin 11% had initiated ART treatment compared to 5% of immigrants and 9% of descendants. Immigrants had 56% lower odds of receiving first ART treatment compared to women of Danish origin (odds ratio (OR) 0.44, CI 95% 0.43-0.45), while descendants had 22% lower odds compared to women of Danish origin (OR 0.78, CI 95% 0.72-0.84). Regarding the analysis examining country of origin, results showed that 3-4% of women originating from western countries had received first ART treatment compared to 6-8% of women originating from non-western countries. Women originating from western countries had between 65% and 78% lower odds for receiving first ART treatment compared to women of Danish origin. Odds of receiving ART treatment among women of non-western origin were between 34% and 47% lower compared to women of Danish origin. LIMITATIONS, REASONS FOR CAUTION: Information on the reason for infertility and desire to have children could have provided more insight into existing disparities. Data about the basis for residence could have provided information on reasons for immigration and duration of residence. WIDER IMPLICATIONS OF THE FINDINGS: Infertility and childlessness can have severe consequences for individuals and society, and equal access to fertility treatment is important, particularly in a universal welfare society. The results of this study indicate ethnic disparity in the use of ART treatment, and we encourage further research into the possible causes and barriers to initiate treatment. STUDY FUNDING/COMPETING INTEREST(S): The funding for the establishment of the Danish National ART-Couple II Cohort (DANAC II Cohort) was obtained from the Rosa Ebba Hansen Foundation. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.