Table 4.
Threshold impact analysis of the female age and clinical pregnancy rate/ongoing pregnancy rate.
| Models | CPR | OPR | ||
|---|---|---|---|---|
| OR (95% CI) | P value | OR (95% CI) | P value | |
| Model I | ||||
| One line effect | 0.96 (0.95, 0.97) | < 0.0001 | 0.96 (0.94, 0.97) | < 0.0001 |
| Model II | ||||
| Turning point (K1, K2) | 34 | 34 | ||
| Female age < K1 | 0.99 (0.98, 1.01) | 0.516 | 1.00 (0.98, 1.01) | 0.739 |
| Female age ≥ K2 | 0.90 (0.84, 0.96) | < 0.0001 | 0.84 (0.81, 0.88) | < 0.0001 |
| P value for LRT test* | < 0.001 | < 0.001 | ||
Threshold effect analysis of the female age and pregnancy outcomes. Data were presented as OR (95% CI) P value; Model I, linear analysis; Model II, non-linear analysis. Adjust for infertility years, types of fertilization, infertility factors, AMH, COS protocols, frozen embryos, embryo type, and endometrial thickness. CI confidence interval, OR odds ratio, LRT logarithm likelihood ratio test. *P < 0.05 manifests that Model II is significantly different from Model I.