The incidence, risk factors and maternal and foetal outcomes of uterine rupture during different birth policy periods: an observational study in China

Table 1 Incidence and number of uterine ruptures by maternal age, parity and number previous caesarean sections over different birth policy periods in 438 hospitals, China

Maternal characteristics	One-child policy period	Partial two-child policy period	Universal two-child policy period
Weighted rate, per 100 births^a
Maternal age
< 24	0.02	0.05	0.09
24–29	0.04	0.09	0.16
30–34	0.08	0.21	0.32
≥ 35	0.65	0.24	0.42
Missing	0.04	0.09	0.10
Parity
0	0.01	0.02	0.02
≥ 1
All	0.10	0.23	0.39
1	0.09	0.23	0.38
2	0.13	0.26	0.46
≥ 3	0.14	0.15	0.28
Missing	0.03	0.00	1.21
Previous caesarean sections
0	0.01	0.02	0.02
≥ 1
All	0.30	0.67	1.02
1	0.28	0.64	0.95
≥ 2	0.65	1.18	1.92
Missing	0.02	0.14	1.09
Total	0.05	0.12	0.22
Adjusted odds ratio^a
Maternal age^b
< 24	1	1.79 (1.31–2.45)	2.54 (1.75–3.68)
24–29	1	1.86 (1.40–2.44)	2.90 (1.94–4.35)
30–34	1	2.00 (1.49–2.69)	2.84 (1.82–4.32)
≥ 35	1	2.06 (1.47–2.87)	2.80 (1.72–4.58)
Parity^c
0	1	1.50 (1.12–1.99)	1.89 (1.24–2.88)
≥ 1
All	1	2.05 (1.56–2.70)	3.05 (1.99–4.65)
1	1	2.09 (1.57–2.77)	3.00 (1.92–4.70)
2	1	1.74 (1.31–2.31)	2.75 (1.86–4.06)
≥ 3	1	0.97 (0.56–1.69)	1.83 (1.09–3.06)
Previous caesarean sections^d
0	1	1.45 (1.14–1.85)	1.88 (1.37–2.59)
≥ 1
All	1	2.14 (1.60–2.86)	3.21 (2.06–4.98)
1	1	2.12 (1.57–2.87)	3.06 (1.93–4.85)
≥ 2	1	1.82 (1.36–2.44)	3.20 (2.12–4.84)
Total	1	1.96 (1.53–2.52)	2.89 (1.94–4.29)

^aWeighted for the sampling distribution of the population covered by the Chinese National Maternal Near Miss Surveillance System
^bWe did not adjust for maternal age in the different age groups
^cWe did not adjust for parity in the different parity groups
^dWe did not adjust for previous caesarean sections in different groups of previous caesarean sections

ISSN: 1471-2393