Table 1.
Maternal age, delivery condition, prenatal care, and referral system before and after the two-child policy, n (%)
| Observations | Study group (n = 5895 cases) | Control group (n = 5013 cases) | χ2 | P |
|---|---|---|---|---|
| <35 years old | 4453 (75.5) | 3932 (77.1) | 3.46 | 0.07 |
| 35–40 years old | 1230 (20.9) | 1058 (20.7) | 0.03 | 0.87 |
| >40 years old | 212 (3.6) | 113 (2.2) | 18.21 | 0.00 |
| Multipara | 1786 (30.3) | 869 (17.0) | 262.92 | 0.00 |
| Irregular prenatal care | 89 (1.5) | 47 (0.9) | 7.76 | 0.01 |
| Transferred from a subordinate hospital | 261 (4.4) | 145 (2.8) | 19.35 | 0.00 |
| Patients who were not Beijing residents | 226 (3.8) | 113 (2.2) | 24.01 | 0.00 |