Table 3.
Factors associated with placenta accreta spectrum: results from univariate and logistic regression analyses
| Variable | Univariate analysis | Multivariate analysis | ||||
|---|---|---|---|---|---|---|
| OR | 95% CI | P value | aOR | 95% CI | P value | |
| Placenta previa | 17.13 | 10.48–28.01 | < 0.001 | 12.86 | 7.70–21.45 | < 0.001 |
| ART pregnancy | 8.02 | 5.64–11.39 | < 0.001 | 6.78 | 4.54–10.14 | < 0.001 |
| Maternal smoking status | ||||||
| Never smoker | Ref | – | – | Ref | – | – |
| Quit smoking during early pregnancy | 0.74 | 0.46–1.17 | 0.193 | 0.83 | 0.51–1.35 | 0.452 |
| Smoking during pregnancy | 1.83 | 1.11–3.01 | 0.017 | 1.95 | 1.15–3.31 | 0.013 |
| Number of previous CSs | ||||||
| 0 | Ref | – | – | Ref | – | – |
| 1 | 0.95 | 0.54–1.66 | 0.850 | 0.87 | 0.49–1.53 | 0.618 |
| ≥ 2 | 2.49 | 1.36–4.59 | 0.003 | 2.51 | 1.35–4.67 | 0.004 |
| Uterine anomaly | 5.31 | 1.69–16.70 | 0.004 | 3.97 | 1.24–12.68 | 0.020 |
| Adenomyosis | 3.05 | 0.76–12.35 | 0.118 | 1.77 | 0.41–7.52 | 0.442 |
| Endometriosis | 1.67 | 0.93–2.99 | 0.087 | 0.81 | 0.42–1.55 | 0.525 |
| Uterine myoma | 1.52 | 0.93–2.46 | 0.092 | 1.02 | 0.61–1.69 | 0.951 |
| Maternal age | ||||||
| ≤ 19 years | 1.21 | 0.30–4.87 | 0.792 | 1.68 | 0.38–7.48 | 0.494 |
| 20–24 years | Ref | – | – | Ref | – | – |
| 25–29 years | 0.73 | 0.52–1.02 | 0.062 | 1.05 | 0.56–1.96 | 0.878 |
| 30–34 years | 0.86 | 0.64–1.16 | 0.333 | 1.06 | 0.58–1.95 | 0.848 |
| 35–39 years | 1.46 | 1.08–1.98 | 0.014 | 1.23 | 0.66–2.30 | 0.516 |
| ≥ 40 years | 2.05 | 1.27–3.34 | 0.004 | 1.41 | 0.66–3.01 | 0.373 |
| Number of IAs | ||||||
| 0 | Ref | – | – | Ref | – | – |
| 1 | 1.17 | 0.78–1.76 | 0.442 | 1.30 | 0.85–1.97 | 0.224 |
| ≥ 2 | 1.32 | 0.72–2.43 | 0.369 | 1.29 | 0.68–2.45 | 0.433 |
ART Assisted reproductive technology, IA Induced abortion, OR Odds ratio, CI Confidence interval, aOR Adjusted odds ratio, Ref Reference, CS Cesarean section