Six-year outcome of the national premarital screening and genetic counseling program for sickle cell disease and β-thalassemia in Saudi Arabia

BACKGROUND AND OBJECTIVES: Saudi Arabia has a high prevalence of hereditary hemoglobin disorders. Data has been collected by the Saudi Premarital Screening and Genetic Counseling Program on the prevalence of sickle cell disease and β-thalassemia but the outcomes were not quantified. We used six years of premarital screening data to estimate the burden of sickle disease and β-thalassemia over the program period and to assess the frequency of at-risk marriage detection and prevention. DESIGN AND SETTING: Retrospective review, premarital couples attending premarital and genetic counseling clinics with marriage proposals between 2004 and 2009. METHODS: Blood samples obtained from all couples with marriage proposals between 2004 and 2009 were tested for sickle cell disease and β-thalassemia. Test results were shared with all examinees and genetic counseling was offered for all at-risk couples. Marriage certificates were issued irrespective of the results and compliance with medical advice was voluntary. RESULTS: Out of all men and women examined, 70 962 (4.5%) and 29 006 (1.8%) were carriers or cases of sickle cell disease and β-thalassemia, respectively. While the prevalence of sickle cell disease was constant between 2004 and 2009 (average 45.1 per 1000 examined persons, P=.803), the prevalence of β-thalassemia steadily decreased from 32.9 to 9.0 per 1000 examined persons (P<.001). The frequency of at-risk couples decreased by about 60% between 2004 and 2009 (from 10.1 to 4.0 per 1000 examined persons, P<.001). The frequency of voluntary cancellation of marriage proposals among at-risk couples showed more than 5-fold increase between 2004 and 2009 (from 9.2% to 51.9%, P<.001). The eastern region had 58% of all detected at-risk marriages and showed the greatest decline in detection and increase in prevention over time compared to other regions of Saudi Arabia. CONCLUSION: Six years of premarital screening in Saudi Arabia markedly reduced the number of at-risk marriages, which may considerably reduce the genetic disease burden in Saudi Arabia in the next decades.