| Characteristic | Number of women (n = 57) (%) | Estimated population proportion12 |
| Primiparous | 35 (61) | 42%* |
| Non-white ethnicity | 22 (39) | NA |
| Age <20 | 0 (0) | 7% |
| Age ⩾35 | 14 (25) | 19% |
| Single marital status | 9 (16) | NA |
| Twin pregnancy | 10 (18) | 1% |
| Smoked during pregnancy | 9 (16) | NA |
| Professional or managerial occupation | 14 (29) | NA |
| History of pre-eclampsia | 2 (4) | NA |
| History of AFLP | 1 (2) | NA |
| BMI under 20 | 9 (20) | NA |
| BMI ⩾30 | 3 (7) | NA |
| Pre-eclampsia in the current pregnancy | 10 (18) | NA |
*Married women only.
AFLP, acute fatty liver of pregnancy; BMI, body mass index; NA, data not available from routine national statistics.