Table 1.
Population general characteristics, according to weight gain groups
| Under (91) | Normal (73) | Over (11) | P value | |
|---|---|---|---|---|
| Maternal age | 34 ± 5.55 | 34 ± 5.86 | 34 ± 5.03 | 0.99 |
| Nulliparity | 52 (57.1%) | 44 (60.3%) | 8 (72.7%) | 0.32 |
| Smoker | 3 (3.9%) | 5 (6.8%) | 1 (9.1%) | 0.38 |
| Chronic Hypertension | 1 (1.1%) | 1 (1.4%) | 0 | 0.93 |
| pBMIa | 22.75 ± 4.44 | 23.00 ± 3.29 | 23.97 ± 2.50 | 0.70 |
| 18.5 ≤ pBMIa ≤ 24.9 | 74 (81.3%) | 54 (74.0%) | 6 (54.5%) | 0.11 |
| 25 ≤ pBMIa ≤ 29.9 | 10 (11.0%) | 15 (20.5%) | 5 (45.5%) | 0.01 |
| pBMIa ≥ 30 | 7 (7.7%) | 4 (5.5%) | 0 | 0.57 |
| Medically assisted procreation | 16 (17.6%) | 18 (24.7%) | 4 (36.4%) | 0.26 |
| Mono- Chorionicity | 13 (14.3%) | 11 (15.1%) | 2 (18.2%) | 0.94 |
| Clinical chorionamnionitis | 1 (1.1%) | 0 | 0 | 0.63 |
| Preterm rupture of membranesb | 30 (33.0%) | 13 (17.8%) | 3 (27.3%) | 0.09 |
| Gestational age at delivery (weeks) | 35.3 ± 3.0 | 36.5 ± 2.0 | 35.3 ± 2.0 | 0.002 |
| Vaginal delivery | 34 (37.4%) | 23 (31.5%) | 4 (36.4%) | 0.73 |
| 1st twin birth weight (gr) | 2196.54 ± 592.16 | 2494.11 ± 426.87 | 2374.55 ± 471.63 | 0.002 |
| 2nd twin birth weight (gr) | 2154.89 ± 499.41 | 2392.95 ± 413.94 | 2443.50 ± 334.47 | 0.002 |
Results are reported as means and standard deviations (continuous factors) or numbers and percentages (categorical factors). The p-value of an overall test comparing the three groups is also provided (One-way ANOVA for continuous factors and Chi-square test for categorical factors)
Italic data are statistically significant
apBMI = pre-gestational Body Mass Index; bPreterm rupture of membrane = rupture before 37 weeks