Table 1. Baseline Characteristics.
| Characteristic | No. (%) | |
|---|---|---|
| Sildenafil (n = 108) | Placebo (n = 108) | |
| Age, mean (SD), y | 31 (5.1) | 31 (5.0) |
| BMI, mean (SD) | 26 (4.7) | 26 (5.8) |
| Race/ethnicity, descent | ||
| European | 84 (77.8) | 86 (79.6) |
| African | 7 (6.5) | 11 (10.2) |
| Asian | 2 (1.9) | 5 (4.6) |
| Other | 13 (12.0) | 6 (5.6) |
| Maternal smoking | 13 (12.0) | 10 (9.3) |
| Gestational age at randomization, median (IQR), wk | 24 5/7 (23 3/7 to 25 5/7) | 25 0/7 (22 5/7 to 26 3/7) |
| Ultrasonagraphic examination results, mean (SD) | ||
| Estimated fetal weight, g | 458 (160) | 464 (186) |
| Fetal abdominal circumference, mm | 165 (2) | 164 (26) |
| Sex | ||
| Boys | 51 (47.2) | 59 (54.6) |
| Girls | 57 (52.8) | 48 (44.4) |
| Notching uterine artery (1- or 2-sided) | 61 (56.5) | 64 (59.3) |
| PI | ||
| Umbilical artery >95th percentile | 51 (47.2) | 53 (49.1) |
| Middle cerebral artery <5th percentile | 47 (43.5) | 43 (39.8) |
| End-diastolic flow | ||
| Positive | 73 (67.6) | 65 (60.2) |
| Absent | 27 (25.0) | 33 (30.6) |
| Reversed | 7 (6.5) | 7 (6.5) |
| Pregnancy hypertension | 22 (20.4) | 24 (22.2) |
| Pre-eclampsia | 23 (21.3) | 26 (24.1) |
| HELLP syndrome | 1 (0.9) | 2 (1.9) |
| Blood pressure, mean (SD), mm Hg | ||
| Systolic | 132 (22) | 132 (20) |
| Diastolic | 83 (15) | 83 (15) |
| PGF <5th percentile of reference value, No./total No. (%)a | 56/61 (91.8) | 53/59 (89.8) |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); HELLP, hemolysis, elevated liver enzymes, and low platelets; IQR, interquartile range; PI, Pulsatility Index; PGF, placental growth factor.
a
Reference value was 106.54 pg/L; 5th percentile of reference population.