Age (y) | | | | (NS) |
⩽19 | 51/889 (6) | 67/890 (8) | 0.80 (0.52 to 1.11) | NS |
20–29 | 530/889 (60) | 527/890 (59) | 1 | – |
30–39 | 223/889 (25) | 213/890 (24) | 1.00 (0.83 to 1.30) | NS |
⩾40 | 85/889 (9) | 83/890 (9) | 1.00 (0.74 to 1.41) | NS |
Marital status | | | | (0.005) |
Never married | 592/867 (68) | 601/864 (69.5) | 1 | – |
Married/de facto | 139/867 (16) | 169/864 (19.5) | 0.80 (0.65 to 1.07) | NS |
Separated/divorced/widowed | 136/867 (16) | 94/864 (11) |
1.50 (1.10 to 1.96)
| 0.01 |
Occupation | | | | (<0.05) |
Employed | 450/852 (53) | 492/859 (57) | 1 | – |
Unemployed | 151/852(18) | 124/859 (14) |
1.30 (1.02 to 1.74)
| <0.05 |
Benefits | 34/852 (4) | 23/859 (3) | 1.60 (0.94 to 2.79) | NS |
Home duty | 45/852 (5) | 34/859 (4) | 1.50 (0.91 to 2.30) | NS |
Student | 112/852 (13) | 138/859 (16) | 0.90 (0.67 to 1.74) | NS |
Sex work | 60/852 (7) | 48/859 (6) | 1.40 (0.92 to 2.04) | NS |
Country of birth | | | | (NS) |
Australia/NZ | 452/832 (54) | 504/833 (61) | 1 | – |
N America/Europe | 198/832 (24) | 169/833 (20) | 1.10 (0.43 to 2.74) | NS |
Asia | 132/832 (16) | 123/833 (15) |
1.30 (1.00 to 1.60)
| 0.05 |
Others | 51/832 (6) | 36/833 (4) | 1.20 (0.88 to 1.52) | NS |
Contraceptive used |
Hormonal | 238/835 (29) | 307/822 (37) |
0.70 (0.54 to 0.82)
| <0.0001 |
IUD | 45/835 (5) | 20/822 (2) |
2.30 (1.34 to 3.90)
| <0.01 |
Diaphragm/cervical cap | 24/835 (3) | 24/822 (3) | 1 | – |
Nil/inadequate | 256/835 (31) | 211/822 (26) |
1.30 (1.03 to 1.59)
| <0.05 |
Obstetric history |
Past pregnancy | 489/865 (57) | 391/862 (45) |
1.60 (1.30 to 1.89)
| <0.0001 |
Termination of pregnancy | 291/726 (40) | 226/729 (31) |
1.50 (1.20 to 1.78)
| <0.001 |
Miscarriage | 128/723 (18) | 88/725 (12) |
1.60 (1.18 to 2.06)
| <0.01 |
Live birth | 184/723 (25) | 129/724 (18) |
1.50 (1.19 to 1.88)
| <0.001 |