Table 1.
Basic characteristics of the participants according to the presence or absence of placenta accreta spectrum
| Variable | PAS (+) N = 202 |
PAS (−) N = 90,352 |
P value |
|---|---|---|---|
| Maternal age, mean years (SD) | 32.4 (5.3) | 31.2 (5.0) | < 0.001a |
| Maternal age category, % (n) | |||
| ≤ 19 years | 1.0 (2) | 0.8 (743) | 0.001b |
| 20–24 years | 6.4 (13) | 9.1 (8192) | |
| 25–29 years | 21.8 (44) | 27.7 (25011) | |
| 30–34 years | 32.2 (65) | 35.4 (32025) | |
| 35–39 years | 29.7 (60) | 22.4 (20274) | |
| ≥ 40 years | 8.9 (18) | 4.5 (4107) | |
| Primiparous, % (n) | 37.6 (76) | 40.6 (36643) | 0.397b |
| ART pregnancy, % (n) | 19.3 (39) | 2.9 (2619) | < 0.001b |
| Maternal smoking status, % (n) | |||
| Never smoker | 81.7 (165) | 82.2 (74294) | 0.029b |
| Quit smoking during early pregnancy | 9.9 (20) | 13.0 (11742) | |
| Smoking during pregnancy | 8.4 (17) | 4.8 (4316) | |
| Number of IAs, % (n) | |||
| 0 | 81.2 (164) | 84.2 (76073) | 0.468b |
| 1 | 13.4 (27) | 11.6 (10506) | |
| ≥ 2 | 5.4 (11) | 4.2 (3773) | |
| BMI, kg/m2, % (n) | |||
| < 18.5 | 16.2 (32) | 16.2 (14471) | 0.925b |
| 18.5–24.9 | 72.2 (143) | 73.1 (65362) | |
| ≥ 25 | 11.6 (23) | 10.8 (9618) | |
| Endometriosis, % (n) | 5.9 (12) | 3.7 (3301) | 0.084b |
| Uterine myoma, % (n) | 8.9 (18) | 6.1 (5475) | 0.090b |
| Adenomyosis, % (n) | 1.0 (2) | 0.3 (295) | 0.099c |
| Uterine anomaly, % (n) | 1.5 (3) | 0.3 (256) | 0.021c |
| Gestational age, mean weeks (SD) | 38.7 (2.1) | 38.7 (2.1) | 0.964a |
| Placenta previa, % (n) | 8.9 (18) | 0.6 (513) | < 0.001b |
| Cesarean section, % (n) | 16.8 (34) | 19.3 (17301) | 0.378b |
| Maternal blood transfusion, % (n) | 19.3 (39) | 0.4 (416) | < 0.001b |
PAS Placenta accreta spectrum, SD Standard deviation, ART Assisted reproductive technology, IA Induced abortion, BMI Body mass index
a P value from t-test
b P value from chi-square test
c P value from Fisher exact test
P < 0.05 is statistically significant