Table II.
Hazard ratios and 95% CIs for laparoscopically confirmed endometriosis according to intake of fruits and vegetables by infertility status among 70 835 women in the Nurses’ Health Study II, 1991–2013.
| Intake in servings per day or week | Case definition | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| All women (n = 2609) | Never infertile1 (n = 2114) | Concurrent infertility1 (n = 313) | ||||||||||
| Cases | Age-adjusted HR (95% CI) | Multivariable2 HR (95% CI) | Cases | Multivariable2 HR (95% CI) | Cases | Multivariable2 HR (95% CI) | P het 3 | |||||
| Total fruits and vegetables | ||||||||||||
| ≤2/day | 224 | 1.00 | Referent | 1.00 | Referent | 181 | 1.00 | Referent | 33 | 1.00 | Referent | 0.43 |
| 3/day | 359 | 0.89 | (0.75, 1.05) | 0.91 | (0.77, 1.07) | 298 | 0.92 | (0.76, 1.11) | 39 | 0.79 | (0.49, 1.27) | |
| 4/day | 455 | 0.88 | (0.75, 1.03) | 0.90 | (0.76, 1.06) | 358 | 0.85 | (0.71, 1.02) | 56 | 0.98 | (0.63, 1.53) | |
| 5/day | 411 | 0.81 | (0.68, 0.95) | 0.82 | (0.69, 0.97) | 337 | 0.81 | (0.67, 0.98) | 44 | 0.81 | (0.51, 1.29) | |
| ≥6/day | 1160 | 0.89 | (0.76, 1.03) | 0.88 | (0.75, 1.03) | 940 | 0.86 | (0.72, 1.02) | 141 | 1.06 | (0.70, 1.61) | |
| Ptrend4 | 0.54 | 0.32 | 0.21 | 0.28 | ||||||||
| Total vegetables | ||||||||||||
| ≤2/day | 711 | 1.00 | Referent | 1.00 | Referent | 568 | 1.00 | Referent | 100 | 1.00 | Referent | 0.75 |
| 3/day | 663 | 0.94 | (0.84, 1.04) | 0.95 | (0.85, 1.06) | 535 | 0.94 | (0.83, 1.05) | 76 | 0.94 | (0.69, 1.28) | |
| 4/day | 508 | 0.93 | (0.82, 1.04) | 0.93 | (0.82, 1.04) | 429 | 0.95 | (0.84, 1.09) | 52 | 0.89 | (0.63, 1.26) | |
| 5/day | 321 | 0.98 | (0.86, 1.13) | 0.97 | (0.84, 1.11) | 264 | 0.97 | (0.83, 1.13) | 32 | 0.93 | (0.61, 1.41) | |
| ≥6/day | 406 | 1.11 | (0.97, 1.27) | 1.04 | (0.91, 1.19) | 318 | 0.99 | (0.85, 1.15) | 53 | 1.22 | (0.84, 1.76) | |
| Ptrend4 | 0.11 | 0.57 | 0.97 | 0.37 | ||||||||
| Green vegetables5 | ||||||||||||
| ≤1/week | 329 | 1.00 | Referent | 1.00 | Referent | 258 | 1.00 | Referent | 53 | 1.00 | Referent | 0.05 |
| 2–6/week | 1486 | 0.99 | (0.87, 1.11) | 0.96 | (0.85, 1.09) | 1219 | 1.00 | (0.87, 1.15) | 162 | 0.80 | (0.58, 1.10) | |
| 1/day | 329 | 0.97 | (0.83, 1.13) | 0.93 | (0.79, 1.08) | 274 | 0.97 | (0.82, 1.16) | 29 | 0.61 | (0.38, 0.97) | |
| >1/day | 465 | 1.01 | (0.87, 1.17) | 0.93 | (0.80, 1.08) | 363 | 0.92 | (0.78, 1.08) | 69 | 1.01 | (0.69, 1.48) | |
| Ptrend4 | 0.81 | 0.28 | 0.18 | 0.78 | ||||||||
| Orange vegetables6 | ||||||||||||
| <1/week | 313 | 1.00 | Referent | 1.00 | Referent | 249 | 1.00 | Referent | 49 | 1.00 | Referent | 0.88 |
| 1/week | 359 | 0.94 | (0.81, 1.10) | 0.97 | (0.83, 1.13) | 285 | 0.94 | (0.79, 1.12) | 48 | 1.05 | (0.70, 1.57) | |
| 2–6/week | 1566 | 0.93 | (0.82, 1.06) | 0.97 | (0.86, 1.10) | 1276 | 0.95 | (0.83, 1.10) | 175 | 1.10 | (0.79, 1.54) | |
| ≥1/day | 371 | 0.96 | (0.82, 1.12) | 0.97 | (0.83, 1.14) | 304 | 0.96 | (0.80, 1.14) | 41 | 1.04 | (0.67, 1.61) | |
| Ptrend4 | 0.94 | 0.88 | 0.88 | 0.94 | ||||||||
| Cruciferous vegetables7 | ||||||||||||
| <1/week | 266 | 1.00 | Referent | 1.00 | Referent | 213 | 1.00 | Referent | 40 | 1.00 | Referent | 0.05 |
| 1/week | 316 | 0.90 | (0.77, 1.06) | 0.92 | (0.78, 1.09) | 261 | 0.93 | (0.78, 1.12) | 35 | 0.84 | (0.53, 1.33) | |
| 2–6/week | 1730 | 0.98 | (0.86, 1.12) | 1.01 | (0.88, 1.15) | 1390 | 0.97 | (0.84, 1.12) | 213 | 1.26 | (0.89, 1.78) | |
| ≥1/day | 297 | 1.16 | (0.98, 1.38) | 1.13 | (0.95, 1.34) | 250 | 1.12 | (0.93, 1.36) | 25 | 0.90 | (0.54, 1.51) | |
| Ptrend4 | 0.006 | 0.03 | 0.05 | 0.94 | ||||||||
| Tomatoes | ||||||||||||
| <1/week | 130 | 1.00 | Referent | 1.00 | Referent | 107 | 1.00 | Referent | 18 | 1.00 | Referent | 0.59 |
| 1/week | 282 | 0.90 | (0.73, 1.10) | 0.94 | (0.76, 1.16) | 225 | 0.90 | (0.71, 1.13) | 41 | 1.20 | (0.68, 2.09) | |
| 2–6/week | 1740 | 0.82 | (0.69, 0.99) | 0.88 | (0.74, 1.06) | 1421 | 0.84 | (0.68, 1.02) | 199 | 1.19 | (0.72, 1.94) | |
| ≥1/day | 457 | 0.91 | (0.74, 1.11) | 0.94 | (0.77, 1.15) | 361 | 0.85 | (0.68, 1.07) | 55 | 1.27 | (0.73, 2.21) | |
| Ptrend4 | 0.63 | 0.81 | 0.53 | 0.52 | ||||||||
| Legumes8 | ||||||||||||
| <1/week | 273 | 1.00 | Referent | 1.00 | Referent | 204 | 1.00 | Referent | 54 | 1.00 | Referent | 0.57 |
| 1/week | 328 | 0.95 | (0.81, 1.12) | 0.99 | (0.85, 1.17) | 270 | 1.06 | (0.88, 1.27) | 40 | 0.82 | (0.54, 1.23) | |
| 2–6/week | 1781 | 0.96 | (0.84, 1.10) | 1.04 | (0.91, 1.18) | 1455 | 1.06 | (0.91, 1.23) | 194 | 1.06 | (0.77, 1.45) | |
| ≥1/day | 227 | 1.03 | (0.86, 1.24) | 1.07 | (0.89, 1.29) | 185 | 1.11 | (0.90, 1.36) | 25 | 1.01 | (0.61, 1.67) | |
| Ptrend4 | 0.52 | 0.39 | 0.43 | 0.63 | ||||||||
| Total fruits | ||||||||||||
| <1/day | 516 | 1.00 | Referent | 1.00 | Referent | 432 | 1.00 | Referent | 59 | 1.00 | Referent | 0.53 |
| 1/day | 218 | 0.98 | (0.84, 1.15) | 1.00 | (0.85, 1.17) | 175 | 0.95 | (0.80, 1.13) | 29 | 1.29 | (0.82, 2.03) | |
| 2/day | 941 | 0.91 | (0.82, 1.02) | 0.92 | (0.82, 1.02) | 753 | 0.87 | (0.77, 0.98) | 106 | 1.07 | (0.77, 1.48) | |
| 3/day | 541 | 0.86 | (0.76, 0.98) | 0.86 | (0.76, 0.98) | 437 | 0.83 | (0.72, 0.95) | 69 | 1.15 | (0.80, 1.66) | |
| ≥4/day | 393 | 0.93 | (0.81, 1.08) | 0.93 | (0.80, 1.07) | 317 | 0.89 | (0.76, 1.05) | 50 | 1.16 | (0.77, 1.77) | |
| Ptrend4 | 0.20 | 0.16 | 0.11 | 0.58 | ||||||||
| Citrus fruits9 | ||||||||||||
| <1/week | 408 | 1.00 | Referent | 1.00 | Referent | 339 | 1.00 | Referent | 56 | 1.00 | Referent | 0.76 |
| 1/week | 308 | 0.82 | (0.70, 0.95) | 0.84 | (0.72, 0.97) | 244 | 0.80 | (0.68, 0.94) | 42 | 0.99 | (0.66, 1.49) | |
| 2–6/week | 1277 | 0.83 | (0.74, 0.93) | 0.86 | (0.76, 0.96) | 1027 | 0.82 | (0.72, 0.93) | 138 | 0.93 | (0.67, 1.28) | |
| ≥1/day | 616 | 0.77 | (0.67, 0.87) | 0.78 | (0.69, 0.89) | 504 | 0.75 | (0.65, 0.87) | 77 | 0.90 | (0.63, 1.29) | |
| Ptrend4 | 0.003 | 0.004 | 0.006 | 0.56 | ||||||||
| Rosaceae fruits10 | ||||||||||||
| <1/week | 167 | 1.00 | Referent | 1.00 | Referent | 141 | 1.00 | Referent | 21 | 1.00 | Referent | 0.18 |
| 1/week | 193 | 0.90 | (0.73, 1.11) | 0.93 | (0.76, 1.15) | 156 | 0.89 | (0.70, 1.11) | 23 | 1.06 | (0.58, 1.92) | |
| 2–6/week | 1548 | 0.86 | (0.73, 1.01) | 0.91 | (0.77, 1.07) | 1238 | 0.84 | (0.71, 1.01) | 198 | 1.31 | (0.83, 2.07) | |
| ≥1/day | 701 | 0.82 | (0.68, 0.97) | 0.87 | (0.73, 1.03) | 579 | 0.83 | (0.69, 1.01) | 71 | 1.05 | (0.63, 1.74) | |
| Ptrend4 | 0.07 | 0.15 | 0.27 | 0.48 | ||||||||
| Fruit juice | ||||||||||||
| <1/week | 426 | 1.00 | Referent | 1.00 | Referent | 368 | 1.00 | Referent | 43 | 1.00 | Referent | 0.02 |
| 1/week | 294 | 1.04 | (0.90, 1.21) | 1.09 | (0.93, 1.26) | 239 | 1.02 | (0.86, 1.20) | 38 | 1.63 | (1.05, 2.53) | |
| 2–6/week | 1128 | 1.01 | (0.90, 1.14) | 1.06 | (0.94, 1.19) | 910 | 0.99 | (0.87, 1.12) | 112 | 1.32 | (0.92, 1.89) | |
| ≥1/day | 761 | 0.91 | (0.80, 1.03) | 0.96 | (0.84, 1.09) | 597 | 0.87 | (0.76, 1.00) | 120 | 1.64 | (1.13, 2.37) | |
| Ptrend4 | 0.02 | 0.09 | 0.01 | 0.03 | ||||||||
1Infertility is defined as attempting to become pregnant for >1 year without success. Cases with ‘no past or concurrent infertility’ are women who never reported infertility. Cases with ‘concurrent infertility’ are women who reported an infertility evaluation in the same follow-up cycle as laparoscopic-confirmation of endometriosis.
2Multivariable model was stratified by age in months at start of follow-up and calendar year of the current questionnaire cycle and was simultaneously adjusted for age at menarche (<10, 10, 11, 12, 13, 14, 15, 16, >16 years), length of menstrual cycle (<26, 26–31, 32–50, 51– days), parity (nulliparous, 1, 2, 3, 4+ pregnancies lasting >6 months), BMI (<19, 19–20.4, 20.5–21.9, 22–24.9, 25–29.9, 30+ kg/m2) and energy (continuous).
3Test for heterogeneity comparing the effect of fruit/vegetable consumption among women with no past or current infertility to those with concurrent infertility.
4Determined using category medians.
5Green vegetables include kale, spinach, and head, romaine or leaf lettuce.
6Orange vegetables include carrots, orange winter squash and yams/sweet potatoes.
7Cruciferous vegetables include broccoli, cauliflower, cabbage and Brussel sprouts.
8Legumes include peas, lima beans, lentils and tofu/soy.
9Citrus fruits include oranges, orange juice, grapefruit and grapefruit juice.
10Rosaceae fruits include prunes, prune juice, apples, apple juice, apple sauce, strawberries and peaches. HR, hazard ratios.