Table 1.
Characteristics of the study population
| Characteristics | Infertile1 | Fertile1 | p-value |
|---|---|---|---|
| Total | 286 (13.4) | 1857 (86.7) | |
| Age (y) | <0.001 | ||
| 20-29 | 65 (8.8) | 677 (91.2) | |
| 30-39 | 103 (14.0) | 634 (86.0) | |
| 40-49 | 118 (17.8) | 546 (82.2) | |
| Ethnicity | 0.531 | ||
| Non-Hispanic white | 111 (14.6) | 649 (85.4) | |
| Non-Hispanic black | 63 (13.6) | 399 (86.4) | |
| Hispanic | 69 (12.1) | 503 (87.9) | |
| Others | 43 (12.3) | 306 (87.7) | |
| Annual family income (US$) | 0.968 | ||
| <20 000 | 57 (13.3) | 372 (86.7) | |
| ≥20 000 | 229 (13.4) | 1485 (86.6) | |
| Education | 0.519 | ||
| Less than high school | 37 (11.4) | 288 (88.6) | |
| High school graduate | 55 (13.4) | 355 (86.6) | |
| More than high school | 194 (13.8) | 1214 (86.2) | |
| Occupation | 0.441 | ||
| Yes | 193 (13.0) | 1295 (87.0) | |
| No | 93 (14.2) | 562 (85.8) | |
| Marital status | <0.001 | ||
| Married | 178 (17.8) | 821 (82.2) | |
| Never married | 43 (7.2) | 557 (92.8) | |
| Widowed/divorced/separated | 65 (12.0) | 479 (88.1) | |
| Total no. of people in the household | 0.026 | ||
| 1 | 13 (13.0) | 87 (87.0) | |
| 2 | 49 (12.1) | 357 (87.9) | |
| 3 | 80 (16.4) | 408 (83.6) | |
| 4 | 56 (12.2) | 402 (87.8) | |
| 5 | 58 (16.1) | 303 (83.9) | |
| 6 | 12 (6.7) | 167 (93.3) | |
| ≥7 | 18 (11.9) | 133 (88.1) | |
| Smoking history | 0.420 | ||
| Never smoked | 196 (13.0) | 1307 (87.0) | |
| Ex-smoker | 40 (16.0) | 210 (84.0) | |
| Current smoker | 50 (12.8) | 340 (87.2) | |
| Alcohol consumption2 | 0.269 | ||
| Yes | 201 (13.9) | 1244 (86.1) | |
| No | 85 (12.2) | 613 (87.8) | |
| Physical activity3 | 0.582 | ||
| Yes | 129 (12.9) | 870 (87.1) | |
| No | 157 (13.7) | 987 (86.3) | |
| Body mass index (kg/m2) | <0.001 | ||
| Underweight (<18.5) | 3 (7.5) | 37 (92.5) | |
| Normal weight (18.5-24.9) | 83 (11.7) | 625 (88.3) | |
| Overweight (25.0-29.9) | 51 (9.5) | 487 (90.5) | |
| Obesity (≥30.0) | 149 (17.4) | 708 (82.6) | |
| Depression4 | 0.467 | ||
| Yes | 205 (13.0) | 1369 (87.0) | |
| No | 81 (14.2) | 488 (85.8) |
Values are presented as number (%).
Infertile if subject responded ‘yes,’ ‘Fertile’ if subject responded ‘no’ to the following question: “Have you ever attempted to become pregnant over a period of at least a year without becoming pregnant?”
Response to the question: “In any one year, have you had at least 12 drinks of any type of alcoholic beverage?”
Response to the question: “In a typical week do you do any moderate-intensity sports, fitness, or recreational activities that cause a small increase in breathing or heart rate such as brisk walking, bicycling, swimming, or volleyball for at least 10 minutes continuously?”
Response to the question: “Over the last 2 weeks, have you been bothered by the following problems: feeling down, depressed, or hopeless?”