Table 2. Demographic and clinical characteristics of the study population stratified according to SPTD at < 32 weeks.
| Variables | Delivery < 32 wk (n = 44) | Delivery ≥ 32 wk (n = 52) | P value | |
|---|---|---|---|---|
| Maternal age, yr | 31.3 ± 2.7 | 32.1 ± 3.6 | 0.222 | |
| Nulliparity | 54.5 (24) | 38.5 (20) | 0.117 | |
| Prior spontaneous preterm birth, < 37 wk | 13.4 (5) | 11.5 (6) | 0.979 | |
| Gestational age at amniocentesis, wk | 21.7 ± 2.4 | 22.2 ± 2.1 | 0.478 | |
| Disease entity | 0.001 | |||
| Cervical insufficiency | 81.8 (36) | 50.0 (26) | ||
| Short cervix | 18.2 (8) | 50.0 (26) | ||
| Cervical length by ultrasound, mm | 2.0 ± 4.9 | 5.9 ± 7.5 | 0.002 | |
| Cervical dilatation, cm | 3 (0–8) | 0.5 (0–8) | < 0.001 | |
| > 2 | 52.3 (23) | 15.4 (8) | < 0.001 | |
| ≤ 2 | 47.7 (21) | 84.6 (44) | ||
| Serum CRP, mg/L | 12.8 ± 15.9 | 5.5 ± 5.6 | 0.127 | |
| Vaginal progesterone therapy | 11.4 (5) | 32.7 (17) | 0.013 | |
| Rescue cerclage | 54.5 (24) | 78.8 (41) | 0.011 | |
| Use of tocolytics | 59.1 (26) | 34.6 (18) | 0.016 | |
| Use of corticosteroids | 43.2 (19) | 26.9 (14) | 0.095 | |
| Use of antibiotics | 97.7 (43) | 82.7 (43) | 0.019 | |
| Clinical chorioamnionitis | 9.1 (4) | 0 (0) | 0.027 | |
| Histologic chorioamnionitisa | 73.8 (31/42) | 22.2 (4/18) | < 0.001 | |
| IAI | 47.7 (21) | 17.3 (9) | 0.001 | |
| Intra-amniotic inflammation | 45.5 (20) | 15.4 (8) | 0.001 | |
| Positive AF cultures | 14.0 (6/43) | 3.9 (2/51) | 0.084 | |
| AF C3a levels, µg/mL | 1.59 ± 0.78 | 1.16 ± 0.46 | 0.003 | |
| AF C5a levels, ng/mL | 7.96 ± 6.39 | 6.01 ± 4.91 | 0.044 | |
| Gestational age at delivery, wk | 24.2 ± 3.7 | 37.1 ± 2.0 | < 0.001 | |
Data are presented as means ± standard deviation, the median (range) or % (number).
SPTD = spontaneous preterm delivery, CRP = C-reactive protein, IAI = intra-amniotic infection and/or inflammation, AF = amniotic fluid.
aData for the histologic evaluation of the placenta were available in 60 (62.5%) of the 96 women because in 5 cases, the delivery took place at another institution and in 31 cases, histologic evaluation of the placenta was not performed because of our institutional policy that only the placentas in cases of preterm delivery are to be sent for histopathologic examination.