TABLE 2.
Maternal (exposure) weight variables by offspring case status
| ASD (n = 1,159) | DD (n = 1,617) | POP (n = 1,633) | ASD vs. POP | DD vs. POP | |
|---|---|---|---|---|---|
| Prepregnancy BMI (kg/m2) | <0.001a | <0.001a | |||
| Mean (SD) | 26.9 (7.4) | 26.4 (6.5) | 25.2 (5.8) | ||
| Prepregnancy BMI (kg/m2) | <0.001b | <0.001b | |||
| Underweight (BMI < 18.5) | 38 (3.3%) | 48 (3.0%) | 53 (3.2%) | ||
| Normal weight (BMI 18.5–24.9) | 548 (47.3%) | 799 (49.4%) | 943 (57.7%) | ||
| Overweight (BMI 25–29.9) | 282 (24.3%) | 400 (24.7%) | 378 (23.1%) | ||
| Obesity Class 1 (BMI 30–34.9) | 136 (11.7%) | 195 (12.1%) | 155 (9.5%) | ||
| Obesity Class 2/3 (BMI 35+) | 155 (13.4%) | 175 (10.8%) | 104 (6.4%) | ||
| GWG-for-GA z score | 0.005a | 0.281a | |||
| Mean (SD) | −0.0 (1.0) | −0.2 (1.1) | −0.1 (1.0) | ||
| GWG-for-GA z scorec | 0.017b | 0.092b | |||
| 1st tertile | 331 (29.8%) | 543 (34.8%) | 508 (32.3%) | ||
| 2nd tertile | 333 (30.0%) | 460 (29.5%) | 519 (33.0%) | ||
| 3rd tertile | 445 (40.1%) | 557 (35.7%) | 546 (34.7%) | ||
| GWG rate (pounds/week) | 0.394d | 0.028d | |||
| Median (IQR) | 1.1 (0.8, 1.5) | 1.0 (0.7, 1.5) | 1.1 (0.8, 1.4) | ||
| GWG rate per IOM guidelines | 0.401b | 0.021b | |||
| Inadequate | 243 (21.5%) | 401 (25.4%) | 353 (22.1%) | ||
| Adequate | 187 (16.6%) | 242 (15.3%) | 292 (18.3%) | ||
| Excessive | 699 (61.9%) | 939 (59.4%) | 951 (59.6%) | ||
| GWG rate (pounds/week)e | 0.018b | 0.045b | |||
| 1st tertile | 331 (29.3%) | 553 (35.0%) | 518 (32.5%) | ||
| 2nd tertile | 356 (31.5%) | 468 (29.6%) | 537 (33.6%) | ||
| 3rd tertile | 442 (39.1%) | 561 (35.5%) | 541 (33.9%) |
Abbreviations: ASD, autism spectrum disorder; DD, developmental disorders; GA, gestational age; GWG, gestational weight gain; IOM, Institute of Medicine; IQR, interquartile range; POP, population-based control group.
ANOVA F test.
χ2 test.
Second tertile corresponds to total GWG (for a 40-week pregnancy) between 13.6 kg and 17.2 kg for a woman with normal prepregnancy BMI. Corresponding values for other BMI categories listed in Supporting Information Table S1.
Wilcoxon Mann-Whitney U test.
Second tertile corresponds to GWG rate between 0.91 and 1.26 pounds/week during the second and third trimesters for a woman with normal prepregnancy BMI. Corresponding values for other BMI categories listed in Supporting Information Table S1.