Table 1.
Characteristics of the Enrolled Participants According to Different BMI Groups (n = 3,174).
| Parameters | Body mass index (kg/m2) | p value | |||
|---|---|---|---|---|---|
| <18.5 (n = 38) | 18.5–24.9 (n = 1,803) | 25.0–29.9 (n = 1,161) | >30 (n = 172) | ||
| Age (years), mean ± SD | 29.13 ± 3.93 | 32.81 ± 6.01 | 33.72 ± 6.22 | 33.04 ± 5.73 | .001 |
| Education level, n (%) | .853 | ||||
| University and above | 20 (52.64) | 921 (51.08) | 607 (52.28) | 86 (50.00) | |
| High school | 9 (23.68) | 461 (25.57) | 302 (26.01) | 40 (23.26) | |
| No higher than junior high school | 9 (23.68) | 421 (23.35) | 252 (21.71) | 46 (26.74) | |
| Monthly income (¥), n (%) | .073 | ||||
| >20,000 | 1 (2.63) | 76 (4.21) | 54 (4.65) | 4 (2.33) | |
| 10,001–20,000 | 5 (13.16) | 217 (12.04) | 154 (13.26) | 16 (9.30) | |
| 5,001–10,000 | 15 (39.47) | 682 (37.83) | 401 (34.54) | 55 (31.98) | |
| 2,000–5,000 | 14 (36.84) | 681 (37.77) | 456 (39.28) | 72 (41.86) | |
| <2,000 | 3 (7.90) | 147 (8.15) | 96 (8.27) | 25 (14.53) | |
| Smoking, n (%) | .569 | ||||
| No | 23 (60.53) | 959 (53.19) | 631 (54.35) | 83 (48.26) | |
| Yes | 15 (39.47) | 844 (46.81) | 530 (45.65) | 89 (51.74) | |
| Alcohol consumption, n (%) | .832 | ||||
| No | 28 (73.68) | 1,018 (56.46) | 669 (57.62) | 101 (58.72) | |
| Yes | 10 (26.32) | 785 (43.54) | 492 (42.38) | 71 (41.28) | |
| Occupation, n (%) | .635 | ||||
| Office work | 17 (44.74) | 762 (42.26) | 498 (42.89) | 61 (35.47) | |
| Manual labor | 12 (31.58) | 763 (42.32) | 475 (40.91) | 87 (50.58) | |
| Other | 9 (23.68) | 278 (15.42) | 188 (16.20) | 24 (13.95) | |
| Marital status, n (%) | .095 | ||||
| Primary | 33 (86.85) | 1540 (85.41) | 971 (83.63) | 141 (81.98) | |
| Remarried | 5 (13.15) | 263 (14.57) | 190 (16.37) | 31 (18.02) | |
| Medical history, n (%) | |||||
| Type of infertility | .002 | ||||
| Primary | 27 (71.05) | 1,182 (65.56) | 810 (69.77) | 130 (75.58) | |
| Secondary | 11 (28.95) | 621 (34.42) | 351 (30.23) | 42 (24.42) | |
| Duration of infertility (years), n (%) | .001 | ||||
| ≤2 | 24 (63.15) | 882 (48.92) | 501 (43.15) | 67 (38.95) | |
| >2 | 14 (36.85) | 921 (51.08) | 660 (56.85) | 105 (61.05) | |
| Cause of infertility, n (%) | .108 | ||||
| Known | 31 (81.58) | 1,293 (71.71) | 833 (71.75) | 143 (83.14) | |
| Unknown | 7 (18.42) | 510 (28.29) | 328 (28.25) | 29 (16.86) | |
| Hypertension, n (%) | .001 | ||||
| No | 38 (100.00) | 1,724 (95.62) | 1,071 (92.25) | 151 (87.79) | |
| Yes | 0 (0.00) | 79 (4.38) | 90 (7.75) | 21 (12.21) | |
| Diabetes, n (%) | .018 | ||||
| No | 38 (100.0) | 1,756 (97.39) | 1,120 (96.47) | 163 (94.77) | |
| Yes | 0 (0.00) | 47 (2.61) | 41 (3.53) | 9 (5.23) | |
| Chronic prostatitis, n (%) | .025 | ||||
| No | 32 (84.21) | 1,501 (83.25) | 992 (85.44) | 153 (88.95) | |
| Yes | 6 (15.79) | 302 (16.75) | 169 (14.56) | 19 (11.05) | |
Note. Data are shown as mean ± standard deviation or n (%). BMI = body mass index.