Table 1.
Maternal baseline characteristics
| Ursodeoxycholic acid (n=304) | Placebo (n=300) | |||
|---|---|---|---|---|
| Age, years | 30·5 (5·6) | 30·8 (5·3) | ||
| Ethnic group | ||||
| White | 247 (81%) | 246 (82%) | ||
| Black | 10 (3%) | 7 (2%) | ||
| Asian | 34 (11%) | 40 (13%) | ||
| Other | 11 (4%) | 7 (2%) | ||
| Not known | 2 (1%) | 0 | ||
| Body-mass index at start of pregnancy (kg/m2), mean (SD) | 27·4 (6·4) | 26·9 (6·1) | ||
| Smoked at start of pregnancy | 33 (11%) | 44 (15%) | ||
| Indices of Multiple Deprivation score: quintile 5*, n/N (%) | 76/289 (26%) | 81/286 (28%) | ||
| Not defined, n | 15 | 14 | ||
| Previous pregnancy of ≥24 weeks' gestation | 178 (59%) | 193 (64%) | ||
| Previous stillbirth | 2 (1%) | 2 (1%) | ||
| History of intrahepatic cholestasis of pregnancy, n/N (%) | 92/175 (53%) | 90/190 (47%) | ||
| Missing, n | 3 | 3 | ||
| Pre-pregnancy liver disease | 3 (1%) | 6 (2%) | ||
| Liver ultrasound at randomisation, n/N (%) | 79/293 (27%) | 78/292 (27%) | ||
| Normal, n/N (%) | 65/77 (84%) | 57/77 (74%) | ||
| Gallstones, n/N (%) | 9/77 (12%) | 12/77 (16%) | ||
| Other abnormality, n/N (%) | 3/77 (4%) | 8/77 (10%) | ||
| Missing result, n | 2 | 1 | ||
| Previous operation for gallstones | 20 (7%) | 17 (6%) | ||
| Pre-pregnancy diabetes | 4 (1%) | 4 (1%) | ||
| Gestational age (weeks), median (IQR)† | 34·4 (32·1–35·9) | 34·4 (31·5–36·0) | ||
| <34 weeks | 133 (44%) | 131 (44%) | ||
| 34 to <37 weeks | 141 (46%) | 141 (47%) | ||
| ≥37 weeks | 30 (10%) | 28 (9%) | ||
| Twin pregnancy† | 18 (6%) | 19 (6%) | ||
| Gestational diabetes | 32 (11%) | 25 (8%) | ||
| Itch score, mean (SD)‡ | 57·1 (25·1) | 59·5 (25·1) | ||
| Medication for pruritus§, n/N (%) | 146/298 (49%) | 137/297 (46%) | ||
| Antihistamine, n/N (%) | 121/298 (41%) | 119/297 (40%) | ||
| Topical emollient, n/N (%) | 102/298 (34%) | 101/297 (34%) | ||
| Ursodeoxycholic acid, n/N (%) | 15/298 (5%) | 13/297 (4%) | ||
| Missing, n | 6 | 3 | ||
| Highest baseline serum concentration before randomisation | ||||
| Bile acid (μmol/L), geometric mean (95% CI)† | 28·1 (26·0–30·3) | 26·9 (24·9–29·0) | ||
| <40 μmol/L | 232 (76%) | 228 (76%) | ||
| ≥40 μmol/L | 72 (24%) | 72 (24%) | ||
| Alanine transaminase, N | 286 | 286 | ||
| Alanine transaminase (U/L), geometric mean (95% CI) | 70·0 (61·5–79·6) | 59·5 (52·0–68·1) | ||
| Aspartate transaminase, N | 47 | 48 | ||
| Aspartate transaminase (U/L), geometric mean (95% CI) | 49·0 (38·4–62·5) | 61·6 (46·8–81·0) | ||
| γ-glutamyl transferase, N | 135 | 138 | ||
| γ-glutamyl transferase (U/L), geometric mean (95% CI) | 23·3 (20·6–26·4) | 21·0 (19·0–23·2) | ||
| Bilirubin, N | 289 | 275 | ||
| Bilirubin (μmol/L), geometric mean (95% CI) | 8·5 (7·9–9·1) | 8·0 (7·4–8·6) | ||
Data are n (%), unless otherwise indicated; N is equal to the total number of participants in the group, unless otherwise indicated; <1% of observations are missing, unless indicated.
*
Quintile 5 represents the most deprived geographical areas; scores are not defined for women from Wales.18
†
Minimisation criterion.
‡
Measured by self-reported worst episode of itch over the past 24 h (mm on visual analogue scale).
§
Not mutually exclusive (some participants used more than one).