Table 1.
Characteristics of the ASD case-control study sample from the Boston Birth Cohort (BBC)
| Neurotypical Controls (n=988) | ASD (n=116) | P | |
|---|---|---|---|
| Gravidity, M (SD) | 2.79 (1.79) | 2.85 (1.93) | 0.701 |
| Parity, M (SD) | 1.04 (1.20) | 0.96 (1.22) | 0.491 |
| Maternal agea, M (SD) | 28.25 (6.55) | 30.11 (6.24) | 0.004* |
| Maternal education, n (%) | 0.281 | ||
| Elementary school | 41 (4.3) | 4 (3.5) | |
| Secondary school | 238 (24.7) | 21 (18.6) | |
| High school/GED | 333 (34.6) | 40 (35.4) | |
| Some college | 203 (21.1) | 33 (29.2) | |
| College degree and above | 148 (15.4) | 15 (13.3) | |
| Maternal marital status, n (%) | 0.570 | ||
| Married | 327 (34.0) | 42 (37.5) | |
| Not Married | 661 (66.0) | 74 (62.5) | |
| Race or Ethnicityb, n (%) | 0.472 | ||
| Black | 615 (62.2) | 73 (62.9) | |
| White | 83 (8.4) | 6 (5.2) | |
| Hispanic | 214 (21.7) | 31 (26.7) | |
| Asian | 20 (2.0) | 2 (1.7) | |
| Other | 56 (5.7) | 4 (3.4) | |
| Maternal smokingc, n (%) | 0.179 | ||
| Never | 817 (85.1) | 88 (78.6) | |
| Some | 48 (5.0) | 9 (8.0) | |
| Continuous | 95 (9.9) | 15 (13.4) | |
| Child sex, n (%) | <0.001* | ||
| Female | 585 (59.2) | 31 (26.7) | |
| Male | 403 (40.8) | 85 (73.3) | |
| Gestational age, mean (SD)d | 38.4 (2.7) | 36.5 (4.6) | <0.001* |
| Birth weight, n (%) | 0.072 | ||
| >2500 grams | 763 (78.9) | 81 (71.1) | |
| <2500 grams | 204 (21.1) | 33 (28.9) |
ASD, autism spectrum disorder; BBC, Boston Birth Cohort; M, mean; SD, standard deviation
Maternal age at time of delivery
Black includes self reported Black, African American, Haitian, Cape Verdean, and Caribbean race and ethnicities. Asian includes Asian and Pacific Islander races. The Other category includes individuals with a mixed or other racial background.
Never smokers were defined as mothers with no history of smoking 6 months prior to conception or during pregnancy; some smoking includes mothers that smoked at some point in the window of 6 months prior to conception and delivery but did not smoke throughout that window; continuous is defined as mothers that smoked starting 6 months prior to and throughout pregnancy.
Defined by sonogram
Denotes statistically significant