Weuve et al. History of hysterectomy was common among MEHP (OR = 0.59; 95% CI, 0.37–0.95) and MEHP concentration versus those in the low- women who reported either condition. the trend across increasing quartiles of MEHP est three quartiles decreased to 0.19 (95% CI, Urinary concentration of MBP was weakly (ptrend = 0.03). 0.05–0.78). For analyses of MEHP and the associated with increased odds of both endo- The associations of urinary MBP and combined outcome, when we made exclusions metriosis (highest vs. lowest three quartiles: MEHP concentrations with these outcomes based on a 5-year interval, the findings were OR = 1.36; 95% CI, 0.77–2.41) and leio- either remained unchanged or became stron- consistent with those from our main analyses. myomata (highest vs. lowest three quartiles: ger when we excluded women whose diagno- In analyses of the oxidative metabolites of OR = 1.56; 95% CI, 0.93–2.61) (Table 3). ses or hysterectomy occurred further in the DEHP (MEHHP and MEOHP), we found When we examined the outcomes as a com- past. For MBP and leiomyomata, when we associations that were consistent with that bined end point, the OR comparing the excluded women whose leiomyomata diagnosis between MEHP and endometriosis, but not highest versus lowest three quartiles of uri- or hysterectomy occurred > 7 years before their with that between MEHP and leiomyomata nary MBP was 1.71 (95% CI, 1.07–2.75). NHANES examination, the OR for women (Table 4). Specifically, the OR of endometriosis Urinary concentration of MEHP was inversely in the highest quartile of MBP concentra- for women in the highest quartile of MEHHP associated with both endometriosis (highest tion versus those in the lowest three quartiles concentration versus those in the lowest three vs. lowest three quartiles: OR = 0.44; 95% increased to 1.86 (95% CI, 0.94–3.68). The quartiles was 0.46 (95% CI, 0.18–1.21), and CI, 0.19–1.02) and leiomyomata (highest vs. corresponding OR for the combined out- the comparable ORs for MEOHP and the lowest three quartiles: OR = 0.63; 95% CI, come increased to 2.16 (95% CI, 1.23–3.77), molar sum of MEHP, MEHHP, and MEOHP 0.35–1.12). For endometriosis, ORs decreased with similar findings with exclusions based on also indicated an inverse association. In contrast, significantly with progressively higher levels of a 5-year interval from diagnosis. For MEHP concentrations of the oxidative metabolites and MEHP (ptrend = 0.05). For the outcomes com- and endometriosis, when we excluded women the molar sum were not consistently associated bined, we found statistically significant inverse whose diagnosis or hysterectomy occurred with leiomyomata. Results for the highest versus associations corresponding to both the contrast > 7 years before their NHANES examination, the lowest three quartiles of MECPP, measured between highest and lowest three quartiles of the OR for women in the highest quartile of only in 2003–2004, were largely consistent with Table 1. Geometric mean urinary creatinine and creatinine-corrected urinary concentration of phthalate metabolites, by diagnosis.a Geometric mean (SE) Women with Women with Women with Percentage of all All women endometriosis uterine leiomyomata neither condition women with levels (n = 1,227) (n = 87) (n = 151) (n = 1,020) < LODb Urinary creatinine (mg/dL) 108.2 (2.5) 108.4 (6.3) 114.0 (5.6) 107.3 (3.0) 0.0 Phthalate metabolites (ng/mg) MBP 26.2 (0.9) 28.9 (4.1) 27.1 (2.6) 25.5 (1.0) 0.5 MEP 216.2 (11.9) 207.0 (27.5) 210.2 (21.9) 219.9 (14.1) 0.2 MEHP 3.3 (0.1) 2.5 (0.4) 2.8 (0.3) 3.4 (0.1)* 20.5 MBzP 14.1 (0.6) 14.4 (2.5) 13.6 (1.2) 14.1 (0.6) 0.6 Oxidative metabolites of DEHP (ng/mg) (2001–2004)c MEHHP 19.4 (1.2) 16.5 (2.8) 20.0 (2.0) 19.7 (1.4) 0.8 MEOHP 13.3 (0.8) 11.5 (1.9) 13.8 (1.4) 13.5 (1.0) 1.7 aNumbers of women with and without a diagnosis do not sum to the total (1,227) because 34 women have both diagnoses, and data on diagnosis of uterine leiomyomata are missing for three women. bPercentages for MEHHP and MEOHP are based on the 2001–2004 sample population (n = 838). cn = 838, 57, 113, and 689 for all women, women with endometriosis, women with uterine leiomyomata, and women with neither condition, respectively. *Significantly higher (p = 0.03) than among women with endometriosis or uterine leiomyomata. Table 2. Characteristics of the study population, by quartile of creatinine-corrected urinary phthalate concentration and by diagnosis status. Race/ethnicity (%) Gynecologic and reproductive history (%) Non- Non- Currently Currently Age at menarche (years) Range Mean Hispanic Hispanic Mexican Other/ Currently breast- uses oral History of Quartile (ng/mg) age black white American mixed Nulliparous pregnant feeding < 12 12–13 > 13 contraceptives hysterectomy MBP Lowest 0.4–15.6 37.5 10.9 72.3 8.1 8.7 25.5 4.5 4.7 24.7 51.3 24.0 14.5 10.7 Second 15.7–25.3 36.1 13.2 72.1 8.6 6.1 30.0 8.0 1.8 23.1 54.0 22.9 14.4 11.8 Third 25.4–41.3 37.5 11.7 64.0 8.1 16.2 26.6 4.9 2.0 23.2 54.3 22.5 12.6 10.6 Highest 41.4–6,429 37.8 13.9 63.2 7.6 15.3 29.1 6.2 2.3 22.2 57.1 20.8 10.9 13.7 MEP Lowest 0.6–100 37.6 8.8 73.4 4.7 13.1 28.0 5.6 5.6 24.0 58.4 17.6 11.7 11.2 Second 101–209 36.9 11.8 72.3 6.3 9.6 27.0 4.9 2.3 27.0 50.4 22.7 13.1 12.3 Third 210–517 37.3 14.0 62.9 10.8 12.3 26.4 6.4 0.9 22.3 51.1 26.6 12.3 14.7 Highest 518–29,986 37.2 15.8* 61.1* 11.2* 11.8 29.9 6.8 1.7* 19.1 57.0 23.9 15.4 8.4 MEHP Lowest 0.2–1.4 38.3 9.7 69.2 9.0 12.1 29.8 5.1 2.9 26.1 54.3 19.6 9.7 11.0 Second 1.5–3.2 37.3 13.2 63.6 7.8 15.3 25.0 7.4 4.0 25.2 47.8 26.9 11.5 10.5 Third 3.3–6.3 36.8 11.5 67.9 9.2 11.4 26.3 3.9 0.9 20.3 58.9 20.8 19.2 14.0 Highest 6.4–538 36.4 15.4 70.8 6.3 7.4 29.9 7.0 2.7 21.1 56.4 22.5 12.5 11.5 MBzP Lowest 0.2–7.7 38.9 12.9 67.4 10.5 9.3 32.2 4.7 2.1 22.7 52.1 25.2 14.6 10.5 Second 7.8–13.1 37.4 12.1 65.2 8.8 10.9 28.7 3.6 2.6 24.7 53.2 22.1 15.4 9.7 Third 13.2–23.2 36.9 12.1 67.5 4.5 12.9 26.1 5.6 2.4 20.4 57.6 22.0 11.6 14.4 Highest 23.3–650 35.9* 12.6 71.1 5.8* 10.5 24.5 9.5* 3.6 25.5 53.5 21.0 10.9 12.1 Endometriosis Yes 40.4 5.3 83.7 3.0 8.0 24.8 2.9 0.1 26.1 55.8 18.1 10.4 49.3 No 36.9* 13.2* 66.2* 8.6* 12.0 28.1 6.2 3.0* 23.0 54.0 23.0 13.4 7.8* Uterine Yes 44.3 18.9 67.1 3.4 10.5 16.6 2.8 1.6 27.1 52.8 20.0 6.5 42.3 leiomyomata No 36.0* 11.4* 67.9 8.1* 11.8 29.8* 6.4 2.9 22.8 54.4 22.8 14.2* 6.4* *Difference across the quartiles or by diagnosis, p < 0.05. 828 118 | number 6 | June 2010 • Environmental Health Perspectives ovlume