TABLE 1.
Down syndrome (Trisomy 21) counts and prevalence (prevalence per 10,000 live births) for 25 US population-based surveillance programs,a 2013–2017
| Live births from all programsa | All pregnancy outcomes from active programsb | |||||
|---|---|---|---|---|---|---|
| Variable values | Count | Prevalence | 95% CIc | Count | Prevalence | 95% CIc |
| Totald | 13,376 | 12.7 | 12.4–12.9 | 6,210 | 13.3 | 13.0–13.6 |
| Case ascertainment methodologya | ||||||
| Active case finding | 6,798 | 12.8 | 12.5–13.1 | 6,210 | 13.3 | 13.0–13.6 |
| Passive case finding | 6,578 | 12.5 | 12.2–12.8 | - | - | - |
| Maternal race/ethnicity | ||||||
| White, non-Hispanic | 6,686 | 11.6 | 11.3–11.9 | 2,574 | 12.3 | 11.8–12.7 |
| Black, non-Hispanic | 1,754 | 11.9 | 11.3–12.4 | 673 | 10.9 | 10.1–11.8 |
| Hispanic | 3,961 | 16.0 | 15.5–16.5 | 2,441 | 15.4 | 14.8–16.0 |
| Asian or Pacific islander, non-Hispanic | 540 | 9.1 | 8.4–9.9 | 246 | 10.8 | 9.5–12.2 |
| American Indian or Alaska native, non-Hispanic | 126 | 12.7 | 10.5–15.1 | 90 | 12.9 | 10.4–15.9 |
| Maternal age (years) | ||||||
| <20 | 446 | 6.9 | 6.2–7.5 | 225 | 6.7 | 5.8–7.6 |
| 20–24 | 1,428 | 6.3 | 6.0–6.6 | 680 | 6.2 | 5.8–6.7 |
| 25–29 | 2,040 | 6.5 | 6.2–6.8 | 930 | 6.9 | 6.4–7.3 |
| 30–34 | 2,952 | 10.4 | 10.0–10.7 | 1,280 | 10.7 | 10.1–11.3 |
| 35–39 | 3,719 | 27.3 | 26.4–28.2 | 1,800 | 32.2 | 30.7–33.7 |
| 40–44 | 2,519 | 87.5 | 84.2–91.0 | 1,173 | 100.1 | 94.4–106.0 |
| 45+ | 264 | 108.9 | 96.2–122.9 | 116 | 135.8 | 112.2–162.8 |
| Child sex | ||||||
| Male | 7,244 | 13.3 | 13.0–13.6 | 3,328 | 13.9 | 13.5–14.4 |
| Female | 6,123 | 12.0 | 11.7–12.3 | 2,855 | 12.5 | 12.1–13.0 |
Contributing programs (total live births = 10,573,314) by case-finding methodology: Active case-finding: Arizona, California, Delaware, Georgia (Metropolitan Atlanta), Iowa, Louisiana, Massachusetts, Minnesota, North Carolina, Oklahoma, Puerto Rico, South Carolina, Texas, Utah; Passive case-finding: Alaska, Colorado, Illinois, Indiana, Kentucky, Michigan, New Jersey, New York, Ohio, Oregon, West Virginia.
Active case finding programs that ascertained more than live births: Arizona, California, Delaware, Georgia (Metropolitan Atlanta), Iowa, Massachusetts, North Carolina, Oklahoma, Puerto Rico, South Carolina, Texas, Utah.
CI: Confidence interval. For prevalence confidence interval is calculated using exact Poisson methodology.
Cases were included when gestational age was greater than or equal to 20 completed weeks gestation. If gestational age was missing birth weight was used as a proxy. Counts across subgroups may not add to the total due to other/unknown categories (not shown).