TABLE 1.
Characteristics of Case Infants/Fetuses and Nonmalformed Control Infants Delivered in Selected Counties in California, 1999–2004
| Cases (n = 659) No. (%)a |
Controls (n = 700) No. (%)a |
|
|---|---|---|
| Maternal race/ethnicity | ||
| Latina US-born | 111 (17) | 155 (22) |
| Latina foreign-born | 279 (42) | 264 (38) |
| White | 165 (25) | 144 (21) |
| Black | 28 (4) | 54 (8) |
| Asian | 52 (8) | 63 (9) |
| Other | 17 (3) | 10 (1) |
| Maternal age; yrs | ||
| <25 | 184 (28) | 215 (31) |
| 25–29 | 150 (23) | 161 (23) |
| 30–34 | 185 (28) | 194 (28) |
| >34 | 139 (21) | 127 (18) |
| Maternal education; yrs | ||
| <12 | 223 (34) | 201 (29) |
| 12 | 123 (19) | 166 (24) |
| 13–15 | 145 (22) | 152 (22) |
| >15 | 161 (24) | 168 (24) |
| Maternal vitamin useb | ||
| No | 278 (42) | 271 (39) |
| Yes | 380 (58) | 427 (61) |
| Maternal diabetes | ||
| None | 580 (88) | 656 (94) |
| Gestational | 47 (7) | 39 (6) |
| Type I | 8 (1) | 1 (0) |
| Type II | 14 (2) | 1 (0) |
| Seizure medication use | ||
| No | 656 (100) | 699 (100) |
| Yes | 3 (0) | 1 (0) |
| Family historyc | ||
| No | 648 (98) | 698 (100) |
| Yes | 11 (2) | 2 (0) |
a
Percentages may not equal 100 owing to missing data or rounding.
b
Refers to use of a vitamin supplement that contained folic acid in the period 2 months before through 2 months after conception.
c
Refers to a history of one of the studied birth defects in the probands’ siblings or parents.