TABLE 4.

Prevalence ratios and 95% confidence intervals for associations of maternal and infant birth characteristics with Turner syndrome.

Characteristic	Cases	Live births	Prevalence ratio (95% CI)
Maternal age
<25 years	644	2,103,546	1.0 (0.9–1.1)
25–29 years	493	1,613,425	1.0 (Reference)
30–34 years	427	1,315,475	1.1 (0.9–1.2)
35–39 years	204	614,645	1.1 (0.9–1.3)
≥40 years	56	140,808	1.3 (1.0–1.7)
Maternal race and ethnicity
Hispanic	568	2,199,288	0.7 (0.6–0.8)
Non-Hispanic Alaska Native, American Indian, Asian, or Pacific Islander	68	295,254	0.6 (0.5–0.8)
Non-Hispanic Black	137	821,185	0.5 (0.4–0.6)
Non-Hispanic White	876	2,425,784	1.0 (Reference)
Birth weight for gestational age
Small	313	622,408	3.9 (3.4–4.5)
Appropriate	554	4,342,689	1.0 (Reference)
Large	129	490,644	2.1 (1.7–2.5)
Year of birth
2000–2002	254	838,896	1.0 (Reference)
2003–2005	243	880,320	0.9 (0.8–1.1)
2006–2008	274	940,718	1.0 (0.8–1.1)
2009–2011	359	1,069,032	1.1 (0.9–1.3)
2012–2014	357	1,101,556	1.1 (0.9–1.3)
2015–2017	385	1,080,587	1.2 (1.0–1.4)