Table 1.
Demographics of the Brisbane cohort (births between 1 July 2005 and 30 June 2009)
| n | % | |
|---|---|---|
| Total births | 114,947 | 100.0 |
| Gender | ||
| Male | 59,317 | 51.6 |
| Female | 55,630 | 48.4 |
| Marital status | ||
| Married/De facto | 98,888 | 86.0 |
| Never married | 14,240 | 12.4 |
| Separated/Divorced | 1,788 | 1.6 |
| Not stated | 31 | < 0.1 |
| Indigenous status | ||
| Indigenous | 2,568 | 2.2 |
| Non-indigenous | 112,301 | 97.7 |
| Not stated | 78 | 0.1 |
| Smoking | ||
| Non-smoker | 94,283 | 82.0 |
| Smoker | 19,845 | 17.3 |
| Not stated | 819 | 0.7 |
| Pregnancy complications | ||
| No complications | 108,946 | 94.8 |
| Pre-eclampsia | 6,001 | 5.2 |
| Previous pregnancies | ||
| 0 | 34,857 | 30.3 |
| 1-2 | 55,670 | 48.4 |
| 3-4 | 17,393 | 15.1 |
| 5+ | 7,027 | 6.1 |
| Mother's age (years), mean (SD) | 29.6 (5.8) | |
| Gestation length (weeks), mean (SD) | 38.8 (2.3) |
SD = Standard deviation