Table 1.

Distributions of anti-rubella antibodies in pregnant women by age

		N, % (95% CI)
	N	Negative (< 8 IU/ml)	equivocal (8- < 11 IU/ml)	Positive (≥11 IU/ml)	Protective (≥10 IU/ml)	P
Total	324	38 (11.7%; 8.7%–15.7%)	19 (5.9%; 3.8%–9.0%)	267 (82.4%; 77.9%–86.1%)	270 (83.3; 78.9%-87.0%)
Age
17-26y	94	11 (11.7%; 6.7%-19.6%)	5 (5.3%; 2.3%–11.9%)	78 (83.0%; 74.1%–89.2%)	79 (84.0%; 75.3%–90.1%)	0.83
27-36y	144	18 (12.5%; 8.1%- 18.9%)	9 (6.3%; 3.3%–11.5%)	117 (81.3%; 74.1%–86.8%)	118 (81.9%; 74.9%–87.4%)
37-46y	86	9 (10.5%; 5.6%- 18.7%)	5 (5.8%; 2.5%–12.9%)	72 (83.7%; 74.5%–90.0%)	73 (84.9%; 75.8%–90.9%)