Table 1 Basic characteristics of participants
Follicle size |  | 12-15 mm (N = 68) | 16-17 mm (N = 171) | ≥ 18 mm (N = 236) | H/χ2 | P |
|---|---|---|---|---|---|---|
Female age |  | 37.5 (33.0-41.8) | 38.0 (32.0–42.0) | 38.0 (33.0–42.0) | 1.708 | 0.426 |
Female BMI |  | 21.7 (20.4–23.3) | 21.5 (20.0-23.3) | 22.3 (20.2–24.8) | 7.712 | 0.021 |
Male age |  | 37.0 (31.3–41.7) | 38.0 (35.0–44.0) | 39.0 (34.0–44.0) | 4.128 | 0.127 |
Male BMI |  | 26.0 (23.7–27.7) | 26.0 (23.0-27.7) | 25.4 (22.8–28.7) | 7.827 | 0.020 |
Infertility duration |  | 2.0 (2.0–6.0) | 3.0 (2.0–7.0) | 4.0 (2.0-7.3) | 0.963 | 0.618 |
History of IVF | No | 18 (27.9) | 62 (36.0) | 99 (41.9) | 4.763 | 0.095 |
| Â | Yes | 49 (72.1) | 110 (64.0) | 137 (58.1) | Â | Â |
Infertility type | Secondary | 32 (47.1) | 83 (48.3) | 109 (46.2) | 0.171 | 0.918 |
| Â | Primary | 36 (52.9) | 89 (51.7) | 127 (53.8) | Â | Â |
Parity | 0 | 40 (58.8) | 96 (56.1) | 134 (56.8) | 1.124 | 0.890 |
| Â | 1 | 16 (23.5) | 35 (20.5) | 48 (20.3) | Â | Â |
|  | ≥ 2 | 12 (17.6) | 40 (23.4) | 54 (22.9) |  |  |
Basic level of FSH | (mIU/mL) | 10.05 (7.22–16.67) | 11.15 (7.03–16.62) | 11.15 (7.94–17.63) | 0.322 | 0.851 |
Basic level of E2 | (pmol/L) | 158.82 (91.75-236.75) | 167.5 (107.75-252.25) | 150.0 (93.0-199.0) | 5.405 | 0.067 |
Basic level of LH | (mIU/mL) | 3.80 (2.46–6.55) | 2.81 (4.11–6.53) | 4.20 (2.49–6.44) | 1.832 | 0.400 |
AMH | (ng/mL) | 0.16 (0.05–0.34) | 0.26 (0.11–0.62) | 0.23 (0.05–0.46) | 6.981 | 0.030 |
Duplicate cycles | No | 48 (70.6) | 113 (66.1) | 174 (73.7) | 2.790 | 0.251 |
| Â | Yes | 20 (29.4) | 58 (33.9) | 62 (26.3) | Â | Â |