Table 1. Demographic, clinical, labour and delivery characteristics of the 165 participants.
| Spontaneous Preterm Birth (SPTB) | Term Birth | SPTL vs PPROM vs Term | SPTB vs Term | |||
|---|---|---|---|---|---|---|
| SPTL | PPROM | SPTL and PPROM | p-value | p-value | ||
| Patient Demographics | ||||||
| Women, n | 15 | 36 | 51 | 114 | ||
| Maternal age, mean years±SD | 31.1±4.9 | 31.3±4.6 | 31.2±4.7 | 31.1±4.7 | 0.910 | 0.850 |
| Pre-pregnancy BMI, mean±SD | 21.9±2.8 | 26.6±9.1 | 25.3±8.0 | 25.8±72 | 0.321 | 0.702 |
| Ethnicity | 0.559 | 0.946 | ||||
| Caucasian, n (%) | 10 | 29 | 39 (76.5) | 85 (74.6) | ||
| Non-Caucasian, n (%) | 5 | 7 | 12 (23.5) | 29 (25.4) | ||
| Smoking during pregnancy | 0.379 | 0.367 | ||||
| Yes, n (%) | 2 | 8 | 10 (19.6) | 14 (12.7) | ||
| No, n (%) | 13 | 28 | 41 (80.4) | 96 (87.3) | ||
| Consumption of alcohol during pregnancy | 0.021 | 0.038 | ||||
| Yes, n (%) | 3 | 4 | 7 (13.7) | 4 (3.6) | ||
| No, n (%) | 12 | 32 | 44 (86.3) | 106 (96.4) | ||
| Clinical Characteristics | ||||||
| Gravidity, mean±SD | 2.7±1.7 | 2.0±1.3 | 2.2±1.4 | 2.0±1.2 | 0.109 | 0.410 |
| Parity | 0.480 | 0.984 | ||||
| Nulliparous, n (%) | 6 | 21 | 27 (52.9) | 60 (54.5) | ||
| Multiparous, n (%) | 9 | 15 | 24 (47.1) | 50 (45.5) | ||
| History of previous PTB | 0.001 | 0.001 | ||||
| Previous PTB, n (%) | 4 | 7 | 11 (21.6) | 4 (3.6) | ||
| No previous PTB, n (%) | 11 | 29 | 40 (78.4) | 106 (96.4) | ||
| History of abortion | 0.002 | 0.001 | ||||
| At least one abortion, n (%) | 5 | 9 | 14 (27.5) | 8 (7.3) | ||
| No previous abortion, n (%) | 10 | 27 | 37 (72.5) | 102 (92.7) | ||
| Mode of conception | 0.188 | 0.267 | ||||
| Spontaneous conception, n (%) | 13 | 34 | 47 (92.2) | 106 (96.4) | ||
| Assisted reproductive technologies, n (%) | 2 | 2 | 4 (7.8) | 4 (3.6) | ||
| Oligohydramnios | 0.800 | 1.00 | ||||
| Present, n (%) | 0 | 2 | 2 (3.9) | 4 (3.6) | ||
| Absent, n (%) | 15 | 34 | 49 (96.1) | 106 (96.4) | ||
| Polyhydramnios | 0.002 | 0.094 | ||||
| Present, n (%) | 3 | 0 | 3 (5.9) | 1 (0.9) | ||
| Absent, n (%) | 12 | 36 | 48 (94.1) | 109 (99.1) | ||
| Gestational diabetes during pregnancy | 0.216 | 0.350 | ||||
| Present, n (%) | 2 | 3 | 5 (9.8) | 5 (4.5) | ||
| Absent, n (%) | 13 | 33 | 46 (90.2) | 105 (95.5) | ||
| Antepartum haemorrhage during pregnancy | 0.004 | 0.009 | ||||
| ≥1 episode of bleeding, n (%) | 7 | 9 | 16 (31.4) | 14 (12.7) | ||
| None, n (%) | 8 | 27 | 35 (68.6) | 96 (87.3) | ||
| Antepartum haemorrhage <20 weeks of gestation (i.e. threatened miscarriage) | 0.419 | 0.353 | ||||
| ≥1 episode, n (%) | 3 | 6 | 9 (17.6) | 12 (10.9) | ||
| None, n (%) | 12 | 30 | 42 (82.4) | 98 (89.1) | ||
| Antepartum haemorrhage >20 weeks of gestation | 0.021 | 0.262 | ||||
| ≥1 episode, n (%) | 6 | 4 | 10 (21.3) | 14 (12.7) | ||
| None, n (%) | 8 | 29 | 37 (78.7) | 96 (87.3) | ||
| Urinary tract infection during pregnancy | <0.001 | 0.001 | ||||
| Present, n (%) | 4 | 3 | 7 (14.0) | 1 (0.9) | ||
| Absent, n (%) | 11 | 32 | 43 (86.0) | 109 (99.1) | ||
| Urinary tract infection before first study sample | 0.029 | 0.029 | ||||
| Present, n (%) | 1 | 2 | 3 (6.0) | 0 (0.0) | ||
| Absent, n (%) | 14 | 33 | 47 (94.0) | 110 (100.0) | ||
| Urinary tract infection before second study sample | <0.001 | 0.003 | ||||
| Present, n (%) | 3 | 2 | 5 (10.0) | 0 (0.0) | ||
| Absent, n (%) | 12 | 33 | 45 (90.0) | 110 (100.0) | ||
| Anaemia during pregnancy | <0.001 | <0.001 | ||||
| Anaemic, n (%) | 4 | 8 | 12 (23.5) | 3 (2.7) | ||
| Non-anaemic, n (%) | 11 | 28 | 39 (76.5) | 107 (97.3) | ||
| Anaemia before first study sample | 0.099 | 0.099 | ||||
| Present, n (%) | 0 | 2 | 2 (3.9) | 0 (0.0) | ||
| Absent, n (%) | 15 | 34 | 49 (96.1) | 110 (100.0) | ||
| Anaemia before second study sample | <0.001 | <0.001 | ||||
| Present, n (%) | 4 | 8 | 12 (23.5) | 1 (0.9) | ||
| Absent, n (%) | 11 | 28 | 39 (76.5) | 109 (99.1) | ||
| Group B Streptococcus in vaginal tract (>36 weeks of gestation) | 0.071 | 0.043 | ||||
| Present, n (%) | 2 | 2 | 4 (7.8) | 24 (21.8) | ||
| Absent, n (%) | 13 | 34 | 47 (92.2) | 86 (78.2) | ||
| Placenta Praevia | 0.143 | 0.327 | ||||
| Present, n (%) | 0 | 3 | 3 (5.9) | 2 (1.8) | ||
| Absent, n (%) | 15 | 33 | 48 (94.1) | 108 (98.2) | ||
| Labour and Delivery Characteristics | ||||||
| Abruptio Placentae | 0.004 | 0.004 | ||||
| Yes, n (%) | 1 | 5 | 6 (11.8) | 1 (0.9) | ||
| No, n (%) | 14 | 31 | 45 (88.2) | 109 (99.1) | ||
| Chorioamnionitis | 0.004 | 0.004 | ||||
| Yes, n (%) | 1 | 5 | 6 (11.8) | 1 (0.9) | ||
| No, n (%) | 14 | 31 | 45 (88.2) | 109 (99.1) | ||
| Gestational age at delivery, mean weeks±SD | 33.5±2.6 | 33.6±2.6 | 33.6±2.6 | 39.2±1.2 | <0.001 | <0.001 |
| Birth weight, mean grams±SD | 2257±551 | 2363±618 | 2332±596 | 3384±473 | <0.001 | <0.001 |
| Neonatal Gender | 0.683 | 0.601 | ||||
| Male, n (%) | 8 | 22 | 30 (58.8) | 71 (64.5) | ||
| Female, n (%) | 7 | 14 | 21 (41.2) | 39 (35.5) | ||
Spontaneous preterm labour (SPTL); preterm prelabour rupture of membranes (PPROM); for continuous variables, one-way ANOVA or Student’s t-test was used for comparison; for categorical variables, Chi-squared test or Fisher’s test (when category size ≤4) was used.