Table 1.
Basic demographic and biological characteristics of infertile females and controls participating in NHANES 2013–2020.
| Total | Infertility | Control | P value | |
|---|---|---|---|---|
| Subjects (%) | 2197 (100) | 295 (13.43) | 1902 (86.57) | |
| Age (years) [mean (SD)] | 34.33 (6.67) | 35.39 (6.14) | 34.17 (6.73) | 0.003 |
| Race (%) | 0.139 | |||
| Mexican American | 408 (18.6) | 43 (14.6) | 365 (19.2) | |
| Other Hispanic | 252 (11.5) | 30 (10.2) | 222 (11.7) | |
| Non-Hispanic White | 653 (29.7) | 106 (35.9) | 547 (28.8) | |
| Non-Hispanic Black | 546 (24.9) | 69 (23.4) | 477 (25.1) | |
| Non-Hispanic Asian | 223 (10.2) | 30 (10.2) | 193 (10.1) | |
| Other Race—Including Multi-Racial | 115 (5.2) | 17 (5.8) | 98 (5.2) | |
| Marital status (%) | 0.001 | |||
| Married/Living with Partner | 1431 (65.1) | 216 (73.2) | 1215 (63.9) | |
| Widowed/Divorced/Separated | 278 (12.7) | 38 (12.9) | 240 (12.6) | |
| Never married | 488 (22.2) | 41 (13.9) | 447 (23.5) | |
| Smoking (%) | 0.730 | |||
| Yes | 493 (22.4) | 69 (23.4) | 424 (22.3) | |
| No | 1704 (77.6) | 226 (76.6) | 1478 (77.7) | |
| Alcohol (%) | 1.000 | |||
| Yes | 19 (0.9) | 3 (1.0) | 16 (0.8) | |
| No | 2178 (99.1) | 292 (99.0) | 1886 (99.2) | |
| History of pregnancy (%) | ||||
| Yes | 2197 (100.0) | 295 (100.0) | 1902 (100.0) | |
| No | 0 (0.00) | 0 (0.00) | 0 (0.00) | |
| History of diabetes (%) | 0.095 | |||
| Yes | 108 (4.9) | 22 (7.5) | 86 (4.5) | |
| No | 2052 (93.4) | 268 (90.8) | 1784 (93.8) | |
| Borderline | 37 (1.7) | 5 (1.7) | 32 (1.7) | |
| History of hypertension (%) | 0.202 | |||
| Yes | 357 (16.2) | 58 (19.7) | 299 (15.7) | |
| No | 1838 (83.7) | 237 (80.3) | 1601 (84.2) | |
| Unknown | 2 (0.1) | 0 (0.00) | 2 (0.1) | |
| Fasting glucose (mmol/L) | 0.628 | |||
| Median (IQR) | 5.33 (5.05, 5.71) | 5.30 (4.94, 5.77) | 5.33 (5.05, 5.66) | |
| Missing (%) | 1147 (52.21) | 161 (54.58) | 986 (51.84) | |
| Total Cholesterol (mg/dL) | 0.106 | |||
| Median (IQR) | 174.00 (155.00, 199.00) | 178.00 (157.25, 203.00) | 174.00 (154.00, 198.00) | |
| Missing (%) | 1 (0.05) | 1 (0.34) | 0 (0.00) | |
| Creatinine, refrigerated serum (mg/dL) | 0.075 | |||
| Median (IQR) | 0.69 (0.62, 0.79) | 0.71 (0.63, 0.80) | 0.69 (0.62, 0.79) | |
| Missing (%) | 1 (0.05) | 0 (0.00) | 1 (0.05) | |
| LDL-cholesterol (mg/dL) | 0.184 | |||
| Median (IQR) | 101.00 (82.00, 120.00) | 101.00 (85.50, 121.50) | 101.00 (81.00, 120.00) | |
| Missing (%) | 1167 (53.12) | 164 (55.59) | 1003 (52.73) | |
| Direct HDL-cholesterol (mg/dL) | 0.303 | |||
| Median (IQR) | 53.00 (44.00, 64.00) | 52.00 (42.25, 63.00) | 53.00 (44.00, 64.00) | |
| Missing (%) | 1 (0.05) | 1 (0.34) | 0 (0.00) | |
| Glycohemoglobin (%) | 0.010 | |||
| Median (IQR) | 5.30 (5.10, 5.60) | 5.40 (5.10, 5.70) | 5.30 (5.10, 5.60) | |
| Missing (%) | 2 (0.09) | 0 (0.00) | 2 (0.11) | |
| BMI (continuous variable) | 0.004 | |||
| Median (IQR) | 28.80 (23.90, 34.95) | 30.45 (24.60, 37.03) | 28.60 (23.90, 34.50) | |
| Missing (%) | 14 (0.64) | 1 (0.34) | 13 (0.68) | |
| BMI (categorical variable) (%) | 0.014 | |||
| < 18.5 | 42 (1.9) | 4 (1.4) | 38 (2.0) | |
| 18.5–24.9 | 614 (28.1) | 77 (26.2) | 537 (28.4) | |
| 25–29.9 | 548 (25.1) | 57 (19.4) | 491 (26.0) | |
| ≥ 30 | 979 (44.8) | 156 (53.1) | 823 (43.6) | |
| Uric acid (continuous variable) (mg/dL) | < 0.001 | |||
| Median (IQR) | 4.40 (3.70, 5.10) | 4.70 (4.00, 5.30) | 4.40 (3.70, 5.10) | |
| Missing (%) | 0 (0.00) | 0 (0.00) | 0 (0.00) | |
| Uric acid (categorical variable) (%) | 0.233 | |||
| 2.4–5.7 | 1903(86.6) | 249(84.4) | 1654(87.0) | |
| < 2.4 | 17(0.8) | 1(0.3) | 16(0.8) | |
| > 5.7 | 277(12.6) | 45(15.3) | 232(12.2) | |
| Uric acid (quartile) (%) | < 0.001 | |||
| Q1 (1.6–3.7) | 560 (25.5) | 52 (17.6) | 508 (26.7) | |
| Q2 (3.7–4.4) | 570 (25.9) | 67 (22.7) | 503 (26.4) | |
| Q3 (4.4–5.1) | 527 (24.0) | 84 (28.5) | 443 (23.3) | |
| Q4 (5.1–18.0) | 540 (24.6) | 92 (31.2) | 448 (23.6) | |
LDL-cholesterol low-density lipoprotein cholesterol, direct HDL-cholesterol direct high-density lipoprotein cholesterol, BMI body mass index. Significant values are in [bold].