Table 3.
Results of linear regression analysis (unadjusted and adjusted) for the relationship between patterns of oral contraceptive use and IGF-1 levels (ng/ml) for women aged 18 to 21 years.
| Unadjusted | Adjusteda | |||||||
|---|---|---|---|---|---|---|---|---|
| No. | Mean (SD) | Beta | 95%CI | P | Beta | 95%CI | P | |
| OC Use | ||||||||
| Never | 100 | 336.8 (111.5) | Reference | 0.002 | Reference | 0.0004 | ||
| Ever | 80 | 288.7 (87.6) | -48.1 | -78.2, -18.0 | -57.2 | -88.7, -25.8 | ||
| Never | 100 | 336.8 (111.5) | Reference | 0.007 | Reference | 0.002 | ||
| Past | 29 | 295.6 (82.8) | -41.2 | -83.6, 1.2 | -51.7 | -94.6, -8.8 | ||
| Current | 51 | 284.7 (90.8) | -52.1 | -86.6, -17.5 | -60.2 | -95.5, -24.9 | ||
| Ever Users | ||||||||
| Age at first use | ||||||||
| 10 to 15 years | 11 | 316.6 (103.4) | 43.1 | -23.2, 109.3 | 0.44 | 34.2 | -36.7, 105.0 | 0.61 |
| 16 to 18 years | 50 | 288.3 (87.9) | 14.7 | -32.4, 61.8 | 17.4 | -44.7, 54.1 | ||
| 19 to 21 years | 19 | 273.6 (77.2) | Reference | Reference | ||||
| Time since last use | ||||||||
| Current | 51 | 284.7 (90.8) | Reference | 0.67 | Reference | 0.60 | ||
| < 1 year | 11 | 310.6 (29.3) | 25.9 | -32.5, 84.3 | 28.7 | -30.0, 87.4 | ||
| ≥ 1 year | 18 | 286.4 (102.7) | 1.7 | -46.5, 49.9 | -1.7 | -50.8, 47.5 | ||
| Total duration of use | ||||||||
| < 1 year | 12 | 273.6 (78.8) | -14.8 | -76.3, 46.6 | 0.80 | -11.8 | -77.3, 53.7 | 0.82 |
| 1 to 2 years | 42 | 293.2 (86.7) | 4.7 | -39.2, 48.7 | 7.0 | -37.6, 51.6 | ||
| >2 years | 26 | 288.4 (95.1) | Reference | Reference | ||||
a Adjusted for age (18 vs. 19 to 21) and ethnicity (East Asian, South Asian, Other/Mixed vs. European)