TABLE 4.
Risk factors for visually and histologically confirmed endometriosis, ENDO Study, 2007 through 2009 (n = 473), sensitivity analysis
| Risk factor | Operative cohort | |
|---|---|---|
| Unadjusted OR (95% CI) | Adjusteda OR (95% CI) | |
| Sociodemographic | ||
| Age, y | 0.97 (0.93–1.00) | — |
| Above poverty level (yes/no)b | 0.90 (0.41–2.02) | 1.07 (0.47–2.45) |
| College educated (yes/no) | 1.25 (0.62–2.49) | 1.35 (0.67–2.73) |
| Reproductive history | ||
| Gravid (vs nulligravid) | 0.32 (0.19–0.55) | 0.31 (0.17–0.56) |
| Parous (vs nulliparous) | 0.30 (0.17–0.52) | 0.27 (0.15–0.49) |
| Infertility history (yes/no) | 2.43 (1.40–4.20) | 2.39 (1.38–4.16) |
| Age at first consenting sex, y | 1.11 (1.04–1.18) | 1.11 (1.04–1.19) |
| Surgical indication for laparoscopy (pelvic pain vs other) | 3.01 (1.74–5.22) | 2.82 (1.59–4.99) |
| Menstruation (past 12 mo) | ||
| Age at menarche, y | 1.05 (0.90–1.23) | 1.04 (0.89–1.22) |
| Mean no. of periodsc | 1.01 (0.97–1.04) | 1.01 (0.98–1.04) |
| Mean cycle length, dc | 1.00 (0.98–1.01) | 0.99 (0.98–1.01) |
| Mean length shortest cycle, dc | 1.00 (0.99–1.01) | 1.00 (0.99–1.01) |
| Mean length longest cycle, dc | 1.00 (0.99–1.01) | 1.00 (0.99–1.01) |
| Dysmenorrhea (yes/no) | 3.49 (1.06–11.5) | 3.11 (0.94–10.3) |
| Pelvic pain (yes/no) | 1.72 (1.02–2.91) | 1.63 (0.96–2.76) |
| Body mass index, kg/m2 | 0.94 (0.90–0.98) | 0.94 (0.90–0.98) |
Cl, confidence interval; OR, odds ratio.
a
Adjusted for age (y) and site;
b
Based upon 2007 HHS Poverty Guidelines accounting for numbers of persons in household for 48 contiguous states and District of Columbia;
c
Among women with ≥1 menstrual cycles in past 12 mo.
Peterson. Risk factors associated with endometriosis. Am J Obstet Gynecol 2013.