Table 1.
Maternal characteristics of the Chinese and Australian pregnancies
| China (n = 480) | Australia (n = 492) | |
|---|---|---|
| Nulliparity | 308 (64.2%) | 170 (34.6%) |
| Maternal age; median (interquartile range; range) | 29 (26–36; 17–49) | 35 (31–39; 17–48) |
| Ethnicity | ||
| Chinese | 480 | N/A |
| Caucasian | N/A | 282 |
| Asian | N/A | 9 |
| Aboriginal | N/A | 85 |
| Did not answer | N/A | 116 |
| Smoking in pregnancy | 3 (1%) | 66 (13.4%) |
| Preterm birth | 63 (13.1%)1 | 52 (10.6%) |
| Threatened abortion | 1 (0.2%) | 15 (3.0%) |
| Gestational age (GA), preterm (min – max) | 28-36 | 21-36 |
| <28 weeks | - | 6 (1.2%) |
| 28-32 weeks | 5 (1.0%) | 3 (0.6%) |
| 33-36 weeks | 58 (12.1%) | 43 (8.7%) |
| 37+ weeks | 417 (86.9%) | 440 (89.4%) |
| Stillbirth | 1 | 8 |
| Premature rupture of membranes (PROM) | 77 (16.0%) | 68 (13.8%) |
| Preterm PROM | 27 (5.6%) | 19 (3.9%) |
1The preterm birth rate in the Chinese sample was enriched from an initial rate of 3.4%.