Table 1.
Baseline characteristics of all FET cycles
| Characteristic | Normal(N = 972) | Overweight(N = 480) | Obesity(N = 228) | Normal vs. Overweight | Overweight vs. Obestiy | Normal vs. Obesity |
|---|---|---|---|---|---|---|
| Age of embryo transfer (years), mean (SD), | 32.82 ± 3.40 | 33.09 ± 3.81 | 33.27 ± 3.61 | 0.152 | 0.542 | 0.076 |
| Duration of infertility (years), mean (SD) | 3.80 ± 2.39 | 4.02 ± 2.80 | 4.21 ± 3.04 | 0.114 | 0.412 | 0.058 |
| BMI of women, mean (SD) | 21.45 ± 1.72 | 26.93 ± 2.21 | 32.13 ± 1.89 | < 0.0001 | < 0.0001 | < 0.0001 |
| Antral follicle count, mean (SD) | 18.48 ± 6.23 | 18.85 ± 6.96 | 17.78 ± 8.01 | 0.306 | 0.069 | 0.218 |
| Infertility causes, n (%) | 0.075 | 0.968 | 0.727 | |||
| PCOS only | 266 (27.38%) | 123 (25.72%) | 59 (25.99%) | |||
| PCOS + male factor | 120 (12.32%) | 55 (11.45%) | 28 (12.19%) | |||
| PCOS + tubal factor | 486 (49.97%) | 242 (50.34%) | 115 (50.62%) | |||
| PCOS + male factor + tubal factor | 74 (7.69%) | 33 (6.93%) | 16 (7.21%) | |||
| PCOS + other factor | 26 (2.64%) | 27 (5.56%) | 10 (3.99%) | |||
| Basal FSH (mIU/mL), median (min-max) | 5.21 (0.32–9.98) | 4.94 (0.26–9.99) | 4.61 (0.45–9.99) | < 0.0001 | 0.031 | 0.002 |
| Basal LH (mIU/mL),median (min-max) | 5.36 (0.19–18.92) | 4.57 (0.16–17.29) | 4.02 (0.28–18.49) | < 0.0001 | 0.031 | < 0.0001 |
| Basal E2 (pg/mL),median (min-max) | 36.00 (10.00–84.00) | 37.00 (10.00–90.00) | 37.00 (10.00–88.00) | 0.546 | 0.929 | 0.618 |
| Basal P (ng/mL),median (min-max) | 0.30 (0.10–0.80) | 0.30 (0.10–0.90) | 0.30 (0.10–0.90) | < 0.0001 | 0.032 | < 0.0001 |
| Previous IVF failures n (%) | 0.177 | 0.941 | 0.585 | |||
| 0 | 693 (71.28%) | 361 (75.17%) | 169 (73.96%) | |||
| 1–2 | 207 (21.28%) | 94 (19.52%) | 46 (19.99%) | |||
| ≥ 3 | 72 (7.44%) | 25 (5.31%) | 13 (6.05%) | |||
| Type of infertility, n (%) | 0.155 | 0.163 | 0.754 | |||
| Primary | 652 (67.04%) | 335 (69.72%) | 156 (68.23%) | |||
| Secondary | 320 (32.96%) | 145 (30.28%) | 72 (31.77%) | |||
| Type of FET cycle | 0.112 | 0.073 | 0.062 | |||
| HRT | 399 (41.07%) | 217 (45.16%) | 107 (46.93%) | |||
| Ovarian stimulation | 573 (58.93%) | 263 (54.84%) | 121 (53.07%) | |||
| Endometrial thickness [17] | 11.28 ± 2.02 | 11.32 ± 2.05 | 11.29 ± 1.98 | 0.532 | 0.329 | 0.835 |
| Fertilization method,n (%) | 0.523 | 0.822 | 0.894 | |||
| IVF | 562 (57.85%) | 287 (59.71%) | 131 (57.29%) | |||
| ICSI | 222 (22.82%) | 97 (20.27%) | 50 (21.96%) | |||
| Half IVF + half ICSI | 188 (19.33%) | 96 (20.02%) | 47 (20.75%) | |||
PCOS Polycystic ovary syndrome, HRT hormone replacement therapy, ICSI Intracytoplasmic sperm injection, FSH follicle-stimulating hormone, LH luteinizing hormone, E2 estradiol; P progestogen. All P values were assessed using χ2 or ANOVA
P <0.05 was considered to be statistically significant