TABLE 1.
Demographic and socioeconomic description of cohorts of infants and their mothers in Shanghai, Cincinnati, and Mexico City at baseline1
| Shanghai | Cincinnati | Mexico City | Omnibus P value2 | |
| n | 120 | 120 | 118 | |
| Household characteristics | ||||
| Married or common union | 118 (98.3)a | 100 (83.3)b | 91 (77.1)b | <0.001 |
| Maternal education | <0.001 | |||
| ≤High school graduate | 22 (18.3) | 6 (5.0) | 110 (93.2) | |
| Attended or graduated from college | 87 (72.5) | 94 (78.3) | 7 (5.9) | |
| Post-college education | 11 (9.2) | 20 (16.7) | 1 (0.8) | |
| Smoked during pregnancy | 1 (0.8)b | 3 (2.5)ab | 11 (9.3)a | 0.003 |
| Household member smoked during pregnancy | 45 (37.5)a | 14 (11.7)b | 58 (49.2)a | <0.001 |
| Employed at time of pregnancy | 85 (71.4)a | 97 (80.8)a | 48 (40.7)b | <0.001 |
| Infant characteristics | ||||
| Sex (male) | 64 (53.3) | 55 (45.8) | 64 (51.2) | 0.49 |
| Birth weight, kg | 3.43 ± 0.47b | 3.56 ± 0.46a | 3.11 ± 0.37c | <0.001 |
| Maternal delivery characteristics | ||||
| Age at delivery, y | 29.3 ± 3.7b | 31.5 ± 5.2a | 24.4 ± 5.6c | <0.001 |
| Prepregnancy BMI, kg/m2 | 20.6 ± 2.3c | 27.5 ± 6.6a | 23.9 ± 3.2b | <0.001 |
| Prepregnancy BMI category | <0.001 | |||
| Underweight (BMI <18) | 11 (9.2) | 0 (0.0) | 1 (0.9) | |
| Normal (BMI 18–24.9) | 103 (86.6) | 54 (45.8) | 76 (67.9) | |
| Overweight (BMI 25–29.9) | 4 (3.4) | 31 (26.3) | 30 (26.8) | |
| Obese (BMI ≥30) | 1 (0.8) | 33 (28.0) | 5 (4.5) | |
| Gestational weight gain, kg | 16.2 ± 5.3a | 13.8 ± 5.1b | 11.2 ± 5.3c | <0.001 |
| Maternal medical conditions at delivery, % yes | ||||
| Any conditions indicated | 51 (42.5)ab | 62 (51.7)a | 36 (30.5)b | 0.004 |
| Gestational diabetes | 4 (3.3)ab | 13 (10.8)a | 3 (2.5)b | 0.009 |
| Asthma | 2 (1.7)b | 14 (11.7)a | 2 (1.7)b | <0.001 |
| Allergies | 42 (35.0)a | 37 (30.8)a | 9 (7.6)b | <0.001 |
| Other diagnosis | 8 (6.7)b | 24 (20.0)a | 25 (21.2)a | 0.003 |
| Delivery type, % vaginal | 36 (30)c | 92 (76.7)a | 72 (61.0)b | <0.001 |
| Time infant in hospital after birth, d | 4.5 ± 1.6a | 2.1 ± 1.0b | 1.8 ± 1.2b | <0.001 |
1
Values are mean ± SD for continuous variables or n (%) for categorical variables, n = 358. Baseline data were available for only 118 mothers in Mexico City. Means or percentages in a row without a common letter differ, P < 0.017.
2
Omnibus P values for comparisons across cohorts presented from ANOVA or χ2 tests.