Table 1 Demographics, pre-existing conditions and pregnancy complications of mothers of ART and non-ART twin sets, Australia, 2007–2011
Non-ART mothers (n = 7541) | ART mothers (n = 2290) | P value (chi-squared test) | |||
|---|---|---|---|---|---|
No. | % | No. | % | ||
Maternal age, years | |||||
Mean ± SD | 30.6 ± 5.4 | 33.9 ± 4.6 | < 0.01* | ||
< 30 | 3151 | 41.8 | 380 | 16.6 | < 0.01 |
30–34 | 2451 | 32.5 | 874 | 38.2 | |
35–39 | 1678 | 22.3 | 795 | 34.7 | |
40–44 | 253 | 3.4 | 184 | 8.0 | |
≥ 45 | 8 | 0.1 | 57 | 2.5 | |
Pre-pregnancy BMI, kg/m2 | |||||
< 20 | 124 | 1.6 | 36 | 1.6 | 0.44 |
20–24.9 | 516 | 6.8 | 213 | 9.3 | |
25–29.9 | 424 | 5.6 | 157 | 6.9 | |
30 + | 334 | 4.5 | 115 | 5.0 | |
Not stated | 6134 | 81.3 | 1769 | 77.2 | |
Parity | |||||
Primiparous | 2773 | 36.8 | 1460 | 63.8 | < 0.01 |
Multiparous | 4768 | 63.2 | 830 | 36.2 | |
Smoking during pregnancy | |||||
Smoked | 1023 | 13.6 | 47 | 2.1 | < 0.01 |
Did not smoke | 4533 | 60.1 | 1709 | 74.6 | |
Not stated | 1985 | 26.3 | 534 | 23.3 | |
Indigenous status of mothers | |||||
Non-Indigenous | 7239 | 96.0 | 2280 | 99.6 | < 0.01 |
Indigenous | 295 | 3.9 | 9 | 0.4 | |
Not stated | 7 | 0.1 | 1 | 0.0 | |
Admitted patient elected accommodation status | |||||
Public | 5014 | 66.5 | 612 | 26.7 | < 0.01 |
Private | 2519 | 33.4 | 1676 | 73.2 | |
Not stated | 8 | 0.1 | 2 | 0.1 | |
Pre-existing hypertension | |||||
Yes | 82 | 1.1 | 34 | 1.5 | 0.13 |
No | 7394 | 98.1 | 2242 | 97.9 | |
Not stated | 65 | 0.9 | 14 | 0.6 | |
Pre-existing diabetes | |||||
Yes | 42 | 0.6 | 13 | 0.6 | 0.96 |
No | 7431 | 98.5 | 2262 | 98.8 | |
Not stated | 68 | 0.9 | 15 | 0.7 | |
Antepartum haemorrhage | |||||
Yes | 340 | 4.5 | 130 | 5.7 | 0.02 |
No | 7201 | 95.5 | 2160 | 94.3 | |
Pregnancy-induced hypertension | |||||
Yes | 634 | 8.4 | 280 | 12.2 | < 0.01 |
No | 6907 | 91.6 | 2010 | 87.8 | |
Gestational diabetes | |||||
Yes | 567 | 7.5 | 222 | 9.7 | < 0.01 |
No | 6974 | 92.5 | 2068 | 90.3 | |