Table 2. Baseline characteristics and clinical pregnancy outcomes of patients by TSH level of 3 mIU/L.
| Characteristic | TSH ≤3 mIU/L | TSH >3 mIU/L | P value |
|---|---|---|---|
| No. of cycles | 5,092 | 996 | |
| Age (years) | 31.17±4.08 | 31.43±4.21 | 0.068 |
| Duration of infertility (years) | 5.78±3.90 | 5.95±3.70 | 0.205 |
| BMI (kg/m2) | 21.88±2.29 | 22.03±2.26 | 0.053 |
| Basal FSH (IU/L) | 5.77±1.91 | 5.62±1.76 | 0.653 |
| Basal E2 (pg/mL) | 41.39±130.43 | 45.39±202.03 | 0.495 |
| AMH (ng/mL) | 3.59±2.86 | 3.40±2.50 | 0.111 |
| TSH (mIU/L) | 1.73±0.62 | 3.70±0.53 | 0.000 |
| FT3 (pmol/L) | 4.39±0.46 | 4.41±0.47 | 0.659 |
| FT4 (pmol/L) | 13.51±1.50 | 13.32±1.52 | 0.594 |
| Duration of Gn (days) | 11.26±1.42 | 11.31±1.47 | 0.280 |
| Total Gn dose (IU) | 2,525.12±800.38 | 2,540.75±829.40 | 0.575 |
| No. of oocytes retrieved | 10.01±4.29 | 10.06±4.35 | 0.774 |
| No. of usable embryos (n) | 3.59±2.56 | 3.99±2.59 | 0.631 |
| Endometrial thickness on day of ET (mm) | 10.09±1.62 | 10.09±1.62 | 0.973 |
| Clinical pregnancy rate (%) | 3,015/5,092 (59.21%) | 561/996 (56.32%) | 0.091 |
| Miscarriage rate (%) | 378/3,015 (12.54%) | 84/561 (14.97%) | 0.114 |
| Live birth rate (%) | 2,637/5,092 (51.79%) | 477/996 (47.89%) | 0.024 |
TSH, thyroid-stimulating hormone; BMI, body mass index; FSH, follicle-stimulating hormone; E2, estradiol; AMH, anti-Mullerian hormone; ET, embryo transfer.