Table 1.
Study population characteristics
| Total (N = 16,019) | Previa | Accreta | |||||
|---|---|---|---|---|---|---|---|
| Without (N = 15,929) | With (N = 90) | p value† | Without (N = 15,980) | With (N = 39) | P value† | ||
| Age (years) | 31.3 ± 5.0 | 31.3 ± 5.0 | 32.9 ± 4.7 | 0.003 | 31.3 ± 5.0 | 34.1 ± 5.2 | 0.002 |
| Smoking habits | |||||||
| Never | 9194 (57) | 9136 (57) | 58 (64) | 9173 (57) | 21 (54) | ||
| Former | 6002 (37) | 5974 (38) | 28 (31) | 0.224 | 5989 (37) | 13 (33) | 1.000 |
| Current | 823 (5) | 819 (5) | 4 (4) | 0.817 | 818 (5) | 5 (13) | 0.057 |
| Smoking habits of partner | |||||||
| Never | 4281 (27) | 4251 (27) | 30 (33) | 4265 (27) | 16 (41) | ||
| Former | 4339 (27) | 4314 (27) | 25 (28) | 0.501 | 4326 (27) | 13 (33) | 0.582 |
| Current | 7399 (46) | 7364 (46) | 35 (39) | 0.122 | 7389 (46) | 10 (26) | 0.013 |
| Drinking habits | |||||||
| No | 14,386 (90) | 14,307 (90) | 79 (88) | 14,355 (90) | 31 (79) | ||
| Yes | 1633 (10) | 1622 (10) | 11 (12) | 0.485 | 1625 (10) | 8 (21) | 0.055 |
| Gravidity | |||||||
| Primigravida | 4758 (30) | 4733 (30) | 25 (28) | 4751 (30) | 7 (18) | ||
| Multigravida | 11,261 (70) | 11,196 (70) | 65 (72) | 0.730 | 11,229 (70) | 32 (82) | 0.117 |
| Parity | |||||||
| Nulliparous | 6385 (40) | 6348 (40) | 37 (41) | 6372 (40) | 13 (33) | ||
| Multiparous | 9634 (60) | 9581 (60) | 53 (59) | 0.829 | 9608 (60) | 26 (67) | 0.513 |
| Number of cesarean deliveries | |||||||
| 0 | 14,576 (91) | 14,496 (91) | 80 (89) | 14,542 (91) | 34 (87) | ||
| 1 | 1111 (7) | 1106 (7) | 5 (6) | 0.833 | 1108 (7) | 3 (8) | 0.744 |
| 2 | 305 (2) | 300 (2) | 5 (6) | 0.030 | 303 (2) | 2 (5) | 0.168 |
| ≥ 3 | 27 (0) | 27 (0) | 0 (0) | 1.000 | 27 (0) | 0 (0) | 1.000 |
Values are mean ± SD or number (%)
†p values for age were obtained using Welch’s t test. p values for other factors were obtained using Fisher’s exact test