Table 2.
Primary, maternal, and perinatal outcomes (number (percent); median [interquartile range])
| Outcome | Placebo (n = 9) | Sildenafil (n = 11) | P-value* |
|---|---|---|---|
| Primary outcome | |||
| Gestational age at delivery (weeks + days) | 29+2 [28+1, 34+1] | 26+4 [25+6, 31+0] | 0.200 |
| Maternal | |||
| Symptomatic hypotension | 0 (0%) | 0 (0%) | NA |
| Pre-eclampsia | 3 (33.3%) | 0 (0%) | 0.211 |
| Mode of delivery | 0.348 | ||
| Termination of pregnancy | 1 | 4 | |
| Vaginal birth | 0 | 1 | |
| Classical Caesarean section | 4 | 4 | |
| Lower segment Caesarean section | 4 | 2 | |
| Haemorrhage requiring transfusion | 1 (11.1%) | 0 (0%) | 0.918 |
| Perinatal | |||
| Fetal growth velocity | |||
| Biparietal diameter (mm/days) | 0.36 [0.32, 0.49] | 0.37 [0.26, 0.39] | 0.508 |
| Head circumference (mm/days) | 1.28 [1.03, 2.07] | 1.21 [1.04, 1.52] | 0.605 |
| Abdominal circumference (mm/days) | 1.05 [0.97, 1.21] | 1.37 [1.10, 1.38] | 0.310 |
| Femur length (mm/days) | 0.28 [0.20, 0.31] | 0.24 [0.16, 0.30] | 0.627 |
| Estimated fetal weight (g/days) | 10.80 [6.07, 11.82] | 7.19 [5.62, 9.40] | 0.667 |
| Deepest vertical amniotic fluid pocket (mm/days) | 0.007 [0.000, 0.009] | 0.013 [0.007, 0.070] | 0.181 |
| Stillbirth | 1 (11.1%) | 4 (36%) | 0.436 |
| Neonatal death | 1 (11.1%) | 1 (9%) | 1 |
| Intact survival† | 7 (77.8%) | 6 (55%) | 0.528 |
| Persistent pulmonary hypertension of the newborn | 0 (0%) | 2 (18%) | 0.164 |
* Fisher’s exact (dichotomous) or Mann Whitney U (continuous) test
† Defined as survival to estimated due date without evidence of severe central nervous system injury (by ultrasound and/or magnetic resonance imaging)