TABLE 1.
Characteristics of women with positive pregnancy tests (N = 785) in the Effects of Aspirin in Gestation and Reproduction study (2007–2011) by tertile of physical activity at baseline.
| Characteristics | METs tertile 1 (0–16.6) n = 261 |
METs tertile 2 (16.6–50.8) n = 262 |
METs tertile 3 (51.3–275.1) n = 262 |
P valuea |
|---|---|---|---|---|
| Age | 28.7 ± 4.7 | 29.1 ± 4.8 | 28.3 ± 4.3 | .17 |
| BMI, kg/m2 | 25.5 ± 6.4 | 25.3 ± 5.9 | 25.8 ± 6.2 | .64 |
| BMI categoryb | .92 | |||
| Underweight (<18.5) | 10 (3.9) | 9 (3.5) | 12 (4.6) | |
| Normal (≥18.5 and <25) | 143 (55.6) | 138 (53.5) | 132 (50.6) | |
| Overweight (≥25 and <30) | 57 (22.2) | 63 (24.4) | 62 (23.8) | |
| Obese (≥30) | 47 (18.3) | 48 (18.6) | 55 (21.1) | |
| Waist-hip ratio | 0.8 (0.1) | 0.8 (0.1) | 0.8 (0.1) | .39 |
| Current partner’s age | 30.2 ± 5.7 | 30.4 ± 5.2 | 29.8 ± 5.1 | .45 |
| Parity | .03 | |||
| Nulliparous | 95 (36.4) | 127 (48.5) | 98 (37.4) | |
| 1 | 110 (42.2) | 89 (34.0) | 101 (38.6) | |
| 2+ | 56 (21.5) | 46 (17.6) | 63 (24.1) | |
| Marital status | .15 | |||
| Living with partner | 12 (4.6) | 10 (3.8) | 6 (2.3) | |
| Married | 241 (92.3) | 249 (95.0) | 254 (97.0) | |
| Other | 8 (3.1) | 3 (1.2) | 2 (0.8) | |
| >High school education | 228 (87.4) | 242 (92.4) | 228 (87.0) | .09 |
| White race | 246 (94.3) | 256 (97.7) | 256 (97.7) | .04 |
| Annual income (US $) | .28 | |||
| ≥100,000 | 97 (37.2) | 118 (45.0) | 106 (40.5) | |
| 75,000–99,999 | 41 (15.7) | 43 (16.4) | 29 (11.1) | |
| 40,000–74,999 | 40 (15.3) | 36 (13.7) | 40 (15.3) | |
| 20,000–39,999 | 62 (23.8) | 53 (20.2) | 68 (26.0) | |
| ≤19,999 | 21 (8.1) | 12 (4.6) | 19(7.3) | |
| Smoking in past year | .82 | |||
| Never | 228 (88.0) | 234 (90.0) | 236 (90.1) | |
| <6 times/week | 20 (7.7) | 19 (7.3) | 16 (6.1) | |
| Daily | 11 (4.3) | 7 (2.7) | 10 (3.8) | |
| Alcohol consumption in past year | .01 | |||
| Never | 168 (64.9) | 163 (62.7) | 194 (75.2) | |
| Sometimes | 85 (32.8) | 86 (33.1) | 62 (24.0) | |
| Often | 6 (2.3) | 11 (4.2) | 2 (0.8) | |
| No. of prior miscarriagesc | .93 | |||
| 1 | 174 (66.7) | 171 (65.3) | 171 (65.3) | |
| 2 | 87 (33.3) | 91 (34.7) | 91 (34.7) | |
| Time since most recent pregnancy loss, months | .55 | |||
| ≤4 | 148 (58.3) | 167 (64.7) | 150 (58.1) | |
| 5–8 | 43 (16.9) | 43 (16.7) | 49 (19.0) | |
| 9–12 | 17 (6.7) | 17 (6.6) | 19 (7.4) | |
| >12 | 46 (18.1) | 31 (12.0) | 40 (15.5) | |
| Walking, hours/week | 1.0 (0–5.0) | 2.3 (0–15.0) | 9 (0–21.0) | < .001 |
| Moderate activity, hours/week | 0 (0–4.0) | 1.5 (0–10) | 10.3 (0–21.0) | < .001 |
| Vigorous activity, hours/week | 0 (0–2.0) | 1.0 (0–5.8) | 2.0 (0–21.0) | < .001 |
| Sitting, hours/day | 6.0 (0–18.0) | 5.0 (0–14.0) | 3.0 (0–15.0) | < .001 |
Note: Values are n (%) for categorical variables and mean ± SD or mean (range) for continuous variables. Data on covariates were missing for BMI (n = 9), current partner’s age (n = 8), smoking in past year (n = 4), alcohol consumption in past year (n = 8), and time from last loss to randomization (n = 15). BMI = body mass index; MET = metabolic equivalent.
P values were calculated from analysis of variance, χ2 test, or Fisher’s exact test, as applicable.
BMI classification (World Health Organization).
Clinically recognized pregnancy losses were documented using a combination of verification from a woman’s physician and medical records.