Comparison of general characteristics between the uninfected screened newborns and the identified congenital cases
| Uninfected screened newborns | Infected cases | p Value | Infected cases with abnormalities at birth† | |
| n=18 330* | n=66 | n=20 | ||
| Mean±SD of mothers' age (years old) | 31.2±4.8 | 29.7±5.9 | NS | 30.6±5.0 |
| Mean±SD of gestation age | 39w1.9d±1w2.1d | 38w3.9d±2w6.1d | NS | 38w3.7d±2w5.2d |
| Mean±SD of birth weight (g) | 3002.9±385.2 | 2756.4±463.7 | NS | 2589.5±515.0 |
| Proportion of low birth weight (<2500 g), % (95% CI) | 7.3 (6.9 to 7.7) | 22.7 (14.1 to 34.3) | <0.001 | 40 (21.8 to 61.4) |
| Proportion of those small for gestational age‡, % (95% CI) | 5.3 (5.0 to 5.6) | 18.2 (10.6 to 29.3) | <0.001 | 30 (14.3 to 52.1) |
| Proportion of the cases with elder sibling(s), % (95% CI) | 48.8 (48.1 to 49.5) | 63.6 (51.6 to 74.2) | <0.02 | 60 (38.6 to 78.2) |
* Uninfected newborns whose information was available from 17 study sites in all six areas.
† Abnormalities include typical clinical manifestations and abnormalities found in brain imaging (see the text).
‡ <−1.5SD in the distribution in the Japanese standard list of birth weight, which is based on sex, number of pregnancy and gestational age.
d, days; w, weeks.