Table 1.
Sociodemographic characteristics and gynecologic surgery history at the time of the index date of women diagnosed with primary infertility between 1980 and 1999 and age-matched female referents.
| Characteristic at the index date† | Primary infertility (N=1001) |
Referent (N=1001) |
p value‡ |
|---|---|---|---|
| Age (years) | --^ | ||
| Mean ± SD | 29.2 ± 4.4 | 29.2 ± 4.4 | |
| Range | (18.4-45.9) | (18.2-46.1) | |
| Race | 0.045 | ||
| American Indian or Alaskan Native | 1 (0.1%) | 6 (0.6%) | |
| Asian | 28 (2.8%) | 23 (2.3%) | |
| Black | 11 (1.1%) | 5 (0.5%) | |
| Native Hawaiian or Pacific Islander | 0 (0.0%) | 1 (0.1%) | |
| Unknown or chose not to disclose | 151 (15.1%) | 191 (19.1%) | |
| White | 797 (79.6%) | 761 (76.0%) | |
| None of the Above | 13 (1.3%) | 14 (1.4%) | |
| Ethnicity | 0.016 | ||
| Hispanic or Latino | 25 (2.5%) | 9 (0.9%) | |
| Not Hispanic or Latino | 726 (72.5%) | 722 (72.1%) | |
| Unknown or chose not to disclose | 250 (25.0%) | 270 (27.0%) | |
| Marital Status | <0.001 | ||
| Single | 15 (1.5%) | 337 (33.7%) | |
| Married | 966 (96.5%) | 646 (64.5%) | |
| Partnered (not Married) | 20 (2.0%) | 10 (1.0%) | |
| Not documented | 0 (0.0%) | 8 (0.8%) | |
| Level of education | <0.001 | ||
| Less than high school | 12 (1.2%) | 33 (3.3%) | |
| High school graduate | 129 (12.9%) | 201 (20.1%) | |
| Some college | 274 (27.4%) | 335 (33.5%) | |
| College (4-yr) graduate | 340 (34.0%) | 226 (22.6%) | |
| Beyond college | 159 (15.9%) | 135 (13.5%) | |
| Not documented | 87 (8.7%) | 71 (7.1%) | |
| Tobacco use | <0.001 | ||
| Current | 153 (15.3%) | 262 (26.2%) | |
| Former | 72 (7.2%) | 94 (9.4%) | |
| Never | 770 (76.9%) | 632 (63.1%) | |
| Not documented | 6 (0.6%) | 13 (1.3%) | |
| BMI (kg/m2) | 0.014 | ||
| Mean ± SD | 24.1 ± 5.7 | 24.8 ± 5.9 | |
| Less than 18.5 | 49 (4.9%) | 26 (2.6%) | |
| 18.5 - 24.9 | 645 (64.4%) | 617 (61.6%) | |
| 25 - 29.9 | 179 (17.9%) | 190 (19.0%) | |
| 30 - 39.9 | 88 (8.8%) | 118 (11.8%) | |
| 40 or more | 27 (2.7%) | 28 (2.8%) | |
| Not documented | 13 (1.3%) | 22 (2.2%) | |
| Gynecologic surgery history | |||
| At least one of the following | 91 (9.1%) | 120 (12.0%) | 0.035 |
| Laparoscopic drilling | 1 (0.1%) | 0 | >.99 |
| Cystectomy | 24 (2.4%) | 15 (1.5%) | 0.15 |
| Unilateral oophorectomy | 13 (1.3%) | 6 (0.6%) | 0.11 |
| Salpingectomy | 11 (1.1%) | 44 (4.4%) | <0.001 |
| Dilation and curettage | 31 (3.1%) | 58 (5.8%) | 0.003 |
| Myomectomy | 7 (0.7%) | 0 | 0.016 |
| Endometriosis resection | 33 (3.3%) | 8 (0.8%) | <0.001 |
†
The index date for each matched pair (case and referent) was defined as the date when the infertility case was first diagnosed with primary infertility.
‡
Comparisons between the two groups were evaluated using the two-sample t-test for BMI and the chi-square test or Fisher’s exact test for all other characteristics.
^
Age was not statistically compared as each infertility case was 1:1 age-matched (±1 y) to a referent woman.