Table 1.
Characteristics of Women Participating in the BioCycle Study (237 Women, 463 Cycles) by Clinical and Biochemical Diagnostic Criteria for LPD
| Luteal Duration |
P Value | Luteal Progesterone |
P Value | |||
|---|---|---|---|---|---|---|
| <10 d | ≥10 d | ≤5 ng/mLa | >5 ng/mL | |||
| Number of cycles, n, % | 41 (8.9) | 422 (91.1) | na | 39 (8.4) | 424 (91.6) | na |
| Demographic and lifestyle characteristics | ||||||
| Age, y | 24.5 ± 7.6 | 28.1 ± 8.3 | .05 | 23.1 ± 6.8 | 28.2 ± 8.3 | .01 |
| 18–22, n, % | 27 (65.9) | 152 (36.0) | .004 | 31 (79.5) | 148 (34.9) | <.001 |
| >22 to 31, n, % | 7 (17.1) | 123 (29.2) | 3 (7.7) | 127 (30.0) | ||
| >31 to 44, n, % | 7 (17.1) | 147 (34.8) | 5 (12.8) | 149 (35.1) | ||
| Percentage body fat | 27.4 ± 4.9 | 29.8 ± 6.1 | .02 | 27.3 (5.1) | 29.8 ± 6.1 | .01 |
| BMI, n, % | ||||||
| Underweight (<18.5 kg/m2) | 0 (0.0) | (3.3) | .65 | 0 (0.0) | 14 (3.3) | .16 |
| Normal (≥18.5 to <25 kg/m2) | 31 (75.6) | 254 (60.2) | 31 (79.5) | 254 (59.9) | ||
| Overweight (≥25 to <30 kg/m2) | 5 (12.2) | 110 (26.1) | 5 (12.8) | 110 (25.9) | ||
| Obese (≥30 kg/m2) | 5 (12.2) | 44 (10.4) | 3 (7.7) | 46 (10.9) | ||
| Race, n, % | ||||||
| White | 34 (82.9) | 247 (58.5) | .02 | 25 (64.1) | 256 (60.4) | .27 |
| Black | 2 (4.9) | 87 (20.6) | 10 (25.6) | 79 (18.6) | ||
| Asian | 5 (12.2) | 56 (13.3) | 2 (5.1) | 59 (13.9) | ||
| Other | 0 (0.0) | 32 (7.6) | 2 (5.1) | 30 (7.1) | ||
| Completed high school, n, % | 40 (97.6) | 367 (87.0) | .07 | 35 (89.7) | 372 (87.7) | .74 |
| Alcohol consumer, n, % | 32 (78.1) | 299 (70.9) | .54 | 27 (69.2) | 304 (71.7) | .97 |
| Smoking, n, % | ||||||
| Current | 2 (4.9) | 62 (14.7) | .63 | 4 (10.3) | 65 (15.3) | .92 |
| Past | 4 (9.8) | 19 (4.5) | 1 (2.6) | 17 (4.0) | ||
| Married, n, % | 7 (17.1) | 120 (28.4) | .18 | 1 (2.6) | 126 (29.7) | .01 |
| Nulligravid, n, % | 33 (80.5) | 278 (66.4) | .13 | 32 (82.1) | 279 (66.3) | .06 |
| Nulliparous, n, % | 36 (87.8) | 292 (70.0) | .03 | 37 (94.8) | 291 (88.7) | .004 |
| Number of cycles, n, % | 41 (8.9) | 422 (91.1) | na | 39 (8.4) | 424 (91.6) | na |
| Sexual activity, n, %2 | ||||||
| Inactive | 25 (61.0) | 191 (45.3) | .19 | 26 (66.7) | 190 (44.8) | .03 |
| Weekly or less | 7 (17.1) | 122 (28.9) | 7 (18.0) | 122 (28.8) | ||
| Greater than weekly | 9 (22.0) | 109 (25.8) | 6 (15.4) | 112 (26.4) | ||
| Past OC use, n, % | 18 (43.9) | 237 (56.1) | .18 | 17 (43.6) | 238 (56.5) | .19 |
| Total energy, kcal | 1588.7 ± 381.0 | 1621.4 ± 439.0 | .53 | 1562.3 ± 459.6 | 1623.6 ± 431.7 | .47 |
| Vigorous exercise, min/d [median (IQR)] | 12.8 (2.0, 26.9) | 8.0 (0.8, 18.6) | .45 | 11.5 (2.1, 21.1) | 8.0 (0.8, 19.0) | .10 |
| Menstrual cycle characteristics | ||||||
| Cycle length, d | 26.6 ± 3.4 | 29.0 ± 3.6 | <.001 | 30.4 ± 6.5 | 28.6 ± 3.2 | .01 |
| Menses length, d | 7.0 ± 2.0 | 7.0 ± 2.3 | .89 | 7.2 ± 2.5 | 7.0 ± 2.2 | .91 |
| Total amount of blood loss, mL [median (IQR)] | 42.0 (15.5, 70.0) | 58.0 (30.0, 88.0) | <.001 | 36.6 (18.5, 72.5) | 57.9 (28.0, 87.8) | .02 |
| Premenstrual spotting, n, % | 1 (2.4) | 10 (2.4) | 1.0 | 0 (0) | 11 (2.6) | .61 |
Abbreviations: BMI, body mass index; IQR, interquartile range; na, not available; OC, oral contraceptive. Repeated-measures analyses (taking into account multiple cycles from the same woman) used to assess associations between demographic, lifestyle, diet, and menstrual cycle characteristics. Mean ± SD unless otherwise noted.
a
International System of Units (SI) conversion for progesterone: 1 ng/mL = 3.18 nmol/L.
b
Sexual activity was defined as vaginal intercourse.