Table 2 Screening of confounding variables for endometriosis and asthma

Age

782/5556

1.00 (0.99–1.01)

0.490

Race

 Mexican American

90/1314

Ref

 Non-Hispanic White

428/2567

2.57 (1.83–3.61)

< 0.001

 Non-Hispanic Black

46/271

2.53 (1.43–4.49)

0.002

 Other Hispanic

184/1151

2.46 (1.68–3.60)

< 0.001

 Other Race

34/253

2.08 (1.22–3.54)

0.008

Education level

 ≤ 12th grade

469/2966

Ref

 College graduate or above

167/1346

0.88 (0.70–1.11)

0.270

 High school grade/GED or equivalent

146/1244

0.77 (0.60–0.98)

0.038

Marital status

 Married

269/1633

Ref

 Divorced/separated

371/3080

0.77 (0.64–0.94)

0.012

 Widowed

11/84

0.71 (0.31–1.66)

0.429

 Never married

131/759

1.04 (0.78–1.39)

0.760

PIR

782/5556

0.93 (0.88–0.99)

0.021

BMI

782/5556

1.03 (1.02–1.04)

< 0.001

Waist circumference

782/5556

1.01 (1.01–1.02)

< 0.001

Cigarettes smoking

 No

426/3446

Ref

 Yes

356/2110

1.39 (1.16–1.66)

0.001

Sexual intercourse

 No

28/266

Ref

 Yes

754/5290

1.28 (0.81–2.01)

0.283

Estrogen and progesterone hormones use

 No

656/4884

Ref

 Yes

126/672

1.42 (1.09–1.86)

0.011

Uterine fibroids

 No

658/4857

Ref

 Yes

124/699

1.41 (1.09–1.83)

0.010

Pregnant history

 No

129/861

Ref

 Yes

653/4695

0.94 (0.75–1.18)

0.602

At least one ovary removed

 No

704/5119

Ref

 Yes

78/437

1.53 (1.10–2.14)

0.013

Birth control pills use

 No

139/1367

Ref

 Yes

643/4189

1.57 (1.22–2.02)

0.001

Current pregnant

 No

610/4374

Ref

 Yes

172/1182

1.09 (0.83–1.44)

0.523