Table 1 Characteristics of 42,196 Singleton Deliveries in Shenzhen 2017–2019
Parameters | Full-term birth (n = 39,428) | Preterm birth (n = 2768) | All (n = 42,196) | P |
|---|---|---|---|---|
Maternal age (years), mean ± SD | 31.22 ± 4.43 | 31.80 ± 4.86 | 31.26 ± 4.46 | < 0.001 |
Maternal age group | < 0.001 | |||
< 35 years, n (%) | 30,029 (76.16%) | 1942 (70.16%) | 31,971 (75.77%) | |
≥ 35 years, n (%) | 9399 (23.84%) | 826 (29.84%) | 10,225 (24.23%) | |
Pre-pregnancy BMI (kg/m2), mean ± SD | 21.06 ± 2.82 | 21.47 ± 3.13 | 21.08 ± 2.84 | < 0.001 |
Pre-pregnancy BMI group a | < 0.001 | |||
Underweight, n (%) | 6479 (16.43%) | 431 (15.57%) | 6910 (16.38%) | |
Normal weight, n (%) | 29,606 (75.09%) | 1993 (72.00%) | 31,599 (74.89%) | |
Overweight, n (%) | 2996 (7.60%) | 299 (10.80%) | 3295 (7.81%) | |
Obesity, n (%) | 347 (0.88%) | 45 (1.63%) | 392 (0.93%) | |
Educational levels | < 0.001 | |||
High school, n (%) | 8317 (24.36%) | 689 (29.57%) | 9006 (24.69%) | |
Bachelor, n (%) | 22,425 (65.69%) | 1458 (62.58%) | 23,883 (65.49%) | |
Master, n (%) | 3398 (9.95%) | 183 (7.85%) | 3581 (9.82%) | |
Nulliparous | 0.068 | |||
No, n (%) | 2137 (5.45%) | 173 (6.28%) | 2310 (5.51%) | |
Yes, n (%) | 37,040 (94.55%) | 2581 (93.72%) | 39,621 (94.49%) | |
Parity, mean ± SD | 0.60 ± 0.61 | 0.62 ± 0.63 | 0.60 ± 0.62 | 0.284 |
Parity group | 0.344 | |||
0, n (%) | 17,851 (46.16%) | 1244 (45.47%) | 19,095 (46.11%) | |
1, n (%) | 18,688 (48.32%) | 1319 (48.21%) | 20,007 (48.31%) | |
2–3, n (%) | 2110 (5.46%) | 170 (6.21%) | 2280 (5.51%) | |
≥ 4, n (%) | 27 (0.07%) | 3 (0.11%) | 30 (0.07%) | |
ART | < 0.001 | |||
No, n (%) | 38,203 (96.89%) | 2612 (94.36%) | 40,815 (96.73%) | |
Yes, n (%) | 1225 (3.11%) | 156 (5.64%) | 1381 (3.27%) | |
GDM | < 0.001 | |||
No, n (%) | 33,236 (84.30%) | 2174 (78.54%) | 35,410 (83.92%) | |
Yes, n (%) | 6192 (15.70%) | 594 (21.46%) | 6786 (16.08%) | |
PE | < 0.001 | |||
No, n (%) | 39,034 (99.00%) | 2479 (89.56%) | 41,513 (98.38%) | |
Yes, n (%) | 394 (1.00%) | 289 (10.44%) | 683 (1.62%) |