Table 1.
Maternal and clinical characteristics of patients with preterm prelabor rupture of the membranes between gestational ages 24+0 and 33+6 weeks
| Characteristic | Delivery ≤ 7 days after admission (n=207) | Delivery > 7 days after admission without a follow-up amniocentesis (n=23) | Delivery > 7 days after admission with a follow-up amniocentesis (n=40) | p-value |
|---|---|---|---|---|
| Maternal age [years, median (IQR)] | 31 (27-36) | 33 (29-37) | 31 (29-34) | 0.47 |
| Primiparous [number (%)] | 98 (47%) | 10 (44%) | 12 (30%) | 0.13 |
| Pre-pregnancy body mass index [kg/m2, median (IQR)] | 23.6 (21.1-26.7) | 24.1 (21.6-28.3) | 23.4 (20.4-25.9) | 0.52 |
| Smoking [number (%)] | 36 (17%) | 3 (13%) | 5 (13%) | 0.67 |
| History of preterm prelabor rupture of the membranes [number (%)] | 13 (6%) | 2 (9%) | 2 (5%) | 0.84 |
| Time interval between rupture of the membranes and amniocentesis [hours, median (IQR)] | 5 (3-10) | 5 (2-10) | 7 (3-14) | 0.25 |
| Gestational age at admission [weeks, median (IQR)] | 32+1 (30+5-33+2) | 30+0 (27+5-31+2) | 28+0 (25+3-31+1) | <0.0001 |
| Gestational age at delivery [weeks, median (IQR)] | 32+4 (30+6-33+4) | 31+4 (29+2-33+1) | 32+0 (29+4-33+2) | 0.12 |
| Latency period [days, median (IQR)] | 2 (1-3) | 12 (9-14) | 17 (12-28) | <0.0001 |
| Amniotic fluid interleukin-6 concentrations at admission [pg/mL, median (IQR)] | 250 (134-887) | 188 (50-327) | 383 (158-1424) | 0.12 |
| Maternal serum C-reactive protein concentrations at admission [mg/L, median (IQR)] | 6.1 (2.7-11.3) | 5.8 (3.1-8.6) | 4.1 (1.6-8.1) | 0.07 |
| Maternal white blood cells count at admission [x109 L, median (IQR)] | 13.0 (10.5-16.0) | 12.2 (9.1-14.5) | 12.1 (10.2-14.2) | 0.05 |
| Vaginal-rectal presence of Streptococcus agalactiae | 25 (12%) | 3 (13%) | 3 (8%) | 0.69 |
| Microbial invasion of the amniotic cavity [number (%)] | 67 (32%) | 5 (22%) | 7 (18%) | 0.06 |
| Intra-amniotic inflammation [number (%)] | 58 (28%) | 3 (13%) | 14 (35%) | 0.17 |
| Intra-amniotic infection [number (%)] | 46 (22%) | 2 (9%) | 7 (18%) | 0.28 |
| Sterile intra-amniotic inflammation [number (%)] | 12 (6%) | 1 (4%) | 7 (18%) | 0.03 |
| Microbial invasion of the amniotic cavity without intra-amniotic inflammation [number (%)] | 23 (11%) | 3 (13%) | 0 (0%) | 0.08 |
| Administration of antibiotics [number (%)] | 207 (100%) | 23 (100%) | 40 (100%) | - |
| Administration of corticosteroids [number (%)] | 201 (97%) | 22 (96%) | 40 (100%) | 0.49 |
| Spontaneous vaginal delivery [number (%)] | 138 (67%) | 7 (30%) | 21 (53%) | 0.001 |
| Cesarean delivery [number (%)] | 68 (33%) | 16 (70%) | 19 (47%) | 0.02 |
| Forceps delivery [number (%)] | 1 (1%) | 0 (0%) | 0 (0%) | 0.86 |
| Birth weight [grams, median (IQR)] | 1880 (1550-2130) | 1700 (1190-1960) | 1630 (1310-2060) | 0.03 |
| Apgar score <7; 5 minutes [number (%)] | 6 (3%) | 2 (9%) | 2 (5%) | 0.34 |
| Apgar score <7; 10 minutes [number (%)] | 5 (2%) | 0 (0%) | 0 (0%) | 0.46 |
Abbreviations:
IQR: interquartile range
Continuous variables were compared using a nonparametric Kruskal-Wallis test. Categorical variables were compared using the chi-square test. Continuous variables are presented as median (IQR) and categorical as number (%).
Statistically significant results are marked in bold.
IQR: interquartile range