Table 1.
Characteristics of the pregnant women, pregnancies, and the newborns and their associations with birth outcomes (multivariable regression analysis).
| Characteristica | Mean or n | ±SD or % | β (SE) | |||||
|---|---|---|---|---|---|---|---|---|
| P | ||||||||
| Birth weight | Birth length | Birth head circumference | Birth chest circumference | Ponderal index | Cephalization index | |||
| Gestational age (weeks); mean, SD (N = 210) | 39.2 | 1.4 | 111.9 (41.3) 0.008 |
0.7 (0.3) 0.01 |
0.08 (0.1) 0.6 |
0.3 (0.2) 0.08 |
0.01 (0.02) 0.7 |
−3.1 (1.0) 0.003 |
| Maternal age (years); mean, SD (N = 210) | 28.6 | 3.9 | 4.3 (14.1) 0.8 |
0.2 (0.1) 0.09 |
0.05 (0.05) 0.3 |
0.03 (0.06) 0.6 |
−0.01 (0.01) 0.08 |
0.04 (0.3) 0.9 |
| Prepregnancy BMI (kg/m2); mean, SD (N = 210) |
22.2 | 3.6 | 27.5 (11.7) 0.02 |
0.005 (0.08) 0.9 |
0.07 (0.04) 0.08 |
0.08 (0.05) 0.07 |
0.01 (0.006) 0.07 |
−0.6 (0.3) 0.03 |
| Maternal height (cm); mean, SD (N = 210) | 167 | 6.0 | 21.9 (7.5) 0.004 |
0.2 (0.05) 0.003 |
0.08 (0.03) 0.003 |
0.07 (0.03) 0.03 |
−0.004 (0.004) 0.3 |
−0.4 (0.2) 0.01 |
| Cotinine (ng/mL); mean, SD (N = 210) |
1.3 | 1.3 | −30.6 (48.2) 0.5 |
−0.3 (0.3) 0.4 |
−0.4 (0.2) 0.02 |
−0.4 (0.2) 0.06 |
0.01 (0.03) 0.3 |
−0.2 (1.1) 0.8 |
| Marital status (N = 210) | ||||||||
| Single | 37 | 17.6 | −27.8 (123.1) | 0.4 (0.8) | 0.3 (0.4) | 0.03 (0.4) | −0.03 (0.07) | 1.5 (2.9) |
| Married | 173 | 82.4 | 0.8 | 0.7 | 0.5 | 0.9 | 0.7 | 0.6 |
| Maternal education (years of education) (N = 209) | ||||||||
| >12 | 141 | 67.5 | 153.8 (111.9) | −0.3 (0.7) | 0.4 (0.4) | 0.02 (0.4) | 0.1 (0.06) | −4.4 (2.7) |
| ≤12 | 68 | 32.5 | 0.2 | 0.7 | 0.3 | 0.9 | 0.08 | 0.2 |
| Employment status in the first trimester (N = 209) | ||||||||
| Employed | 179 | 85.6 | −55.0 (135.5) | −0.7 (0.9) | −0.2 (0.5) | −0.5 (0.5) | 0.04 (0.07) | 1.1 (3.2) |
| Unemployed | 30 | 14.4 | 0.7 | 0.4 | 0.8 | 0.3 | 0.6 | 0.7 |
| Parity (N = 210) | ||||||||
| ≥1 | 87 | 41.4 | 148.8 (116.3) | 0.4 (0.8) | 0.3 (0.4) | 1.2 (0.5) | 0.03 (0.06) | −3.2 (2.8) |
| 0 | 123 | 58.6 | 0.2 | 0.6 | 0.5 | 0.003 | 0.6 | 0.3 |
| Season of the last menstrual period (N = 210) | ||||||||
| October–April | 110 | 52.4 | −5.0 (90.0) | 0.1 (0.6) | −1.1 (0.3) | −0.4 (0.3) | −0.001 (0.05) | −2.8 (2.1) |
| May–September | 100 | 47.6 | 0.9 | 0.8 | 0.001 | 0.3 | 0.9 | 0.2 |
| Place of residence (N = 210) | ||||||||
| >100 thousand inhabitants | 146 | 69.5 | 7.7 (99.0) | 0.4 (0.7) | −0.4 (0.4) | 0.5 (0.4) | −0.03 (0.05) | −0.9 (2.4) |
| ≤100 thousand inhabitants | 64 | 30.5 | 0.9 | 0.5 | 0.3 | 0.3 | 0.6 | 0.7 |
| Alcohol consumption during pregnancy (frequency) (N = 206) | ||||||||
| At least once per month | 13 | 6.2 | −63.0 (170.2) | 0.4 (1.1) | −0.1 (0.6) | −0.9 (0.7) | −0.1 (0.1) | 0.6 (4.1) |
| Less than once per month | 193 | 93.8 | 0.7 | 0.7 | 0.8 | 0.2 | 0.4 | 0.9 |
| Newborns' gender (N = 210) | ||||||||
| Female | 109 | 51.9 | −176.0 (88.6) | −1.9 (0.6) | −0.9 (0.3) | −0.7 (0.3) | 0.08 (0.05) | 3.0 (2.1) |
| Male | 101 | 48.1 | 0.05 | 0.002 | 0.006 | 0.05 | 0.09 | 0.2 |
Numbers may not sum up 210 in all the variables because some values are missing.
Mean and standard deviation (±SD) are presented for continuous variables. N and % are presented for categorical variables.
aFor categorical variables the second category is the reference category in the regression analysis.
β: beta coefficient (and SE standard error) from the multivariable regression analysis.
P : P value from Wald in the multivariable regression analysis.