Table 1.
Maternal baseline characteristics and pregnancy outcomes according to time period.
| Period 1 (n = 220) | Period 2 (n = 227) | Period 3 (n = 188) | P value | |
|---|---|---|---|---|
| Age (years) | 33.3 ± 3.9 | 33.3 ± 3.9 | 33.6 ± 3.8 | 0.751 |
| Body mass index (kg/m2) | 25.1 ± 4.1 | 25.1 ± 4.0 | 25.7 ± 4.0 | 0.243 |
| Multiparity | 90 (40.9) | 79 (34.8) | 60 (31.9) | 0.150 |
| Plurality | 0.0011 | |||
| Singleton | 168 (76.4) | 193 (85.0) | 150 (79.8) | |
| Twin | 51 (23.2) | 34 (15.0) | 31 (16.5) | |
| Triplet | 1 (0.5) | 0 (0) | 7 (3.7) | |
| Antenatal MgSO4 exposure | 46 (20.9) | 141 (62.1) | 28 (14.9) | < 0.00112 |
| Dose of MgSO4 | 54.0 ± 62.6 | 16.4 ± 47.1 | 63.1 ± 53.1 | < 0.00112 |
| Indication of MgSO4 exposure | < 0.00112 | |||
| Neuroprotection | 1 (2.2) | 108 (76.6) | 0 (0) | |
| Severe preeclampsia | 30 (65.2) | 29 (20.6) | 25 (89.3) | |
| Tocolysis | 15 (32.6) | 4 (2.8) | 3 (10.7) | |
| Antenatal corticosteroids exposure | 196 (89.1) | 202 (89.0) | 179 (95.2) | 0.048123 |
| Cycle of corticosteroids | 0.372 | |||
| Incomplete course | 47 (24.0) | 37 (18.3) | 32 (17.9) | |
| Complete course | 111 (56.6) | 132 (65.3) | 116 (64.8) | |
| Rescue course | 38 (19.4) | 33 (16.3) | 31 (17.3) | |
| Tocolysis | ||||
| Ritodrine | 121 (55.0) | 100 (44.1) | 91 (48.4) | 0.067 |
| Atosiban | 85 (38.6) | 77 (33.9) | 64 (34.0) | 0.506 |
| Nifedipine | 74 (33.6) | 54 (23.8) | 39 (20.7) | 0.0073 |
| Indication of delivery | 0.268 | |||
| PTL | 97 (44.1) | 88 (38.8) | 63 (33.5) | |
| PPROM | 64 (29.1) | 77 (33.9) | 65 (34.6) | |
| Maternal–fetal indication | 59 (26.8) | 62 (27.3) | 60 (31.9) | |
| Cesarean delivery | 165 (75.0) | 166 (73.1) | 135 (71.8) | 0.763 |
| Histologic chorioamnionitis | 102 (46.4) | 107 (47.1) | 87 (46.3) | 0.981 |
Data are presented as number (percentage) or mean ± standard deviation.
MgSO4 magnesium sulfate, PTL preterm labor, PPROM preterm premature rupture of membrane.
1Significantly different between period 2 and period 3 (Bonferroni test).
2Significantly different between period 1 and period 2 (Bonferroni test).
3Significantly different between period 1 and period 3 (Bonferroni test).