Table 1 Baseline characteristics of subjects in the 40–49 year age range by contraceptive method use
Characteristics | DMPA (n = 127) | NET-EN (n = 102) | COC (n = 106) | Non-user Controls (n = 161) | P-value |
|---|---|---|---|---|---|
Mean age, years (SD) | 43.6 (2.7) | 43.0 (2.2) | 43.7 (2.5) | 45.4 (2.5) | < 0.001 |
Ethnicity % | |||||
African | 98.4 | 95.2 | 67.0 | 94.4 | 0.007 |
Coloured | 1.6 | 1.0 | 7.5 | 2.5 | |
Indian | 0 | 3.8 | 25.5 | 3.1 | |
Exercise | |||||
No regular exercise (%) | 96.9 | 96.0 | 94.3 | 93 | 0.48 |
Dieted in last 6 months (%) | 0 | 0 | 4.7 | < 1 | 0.003 |
Current smoker (%) | 4.7 | 5.6 | 5.7 | 9.9 | 0.23 |
Parity (median) | 4 | 3 | 3 | 3 | 0.04 |
Ever lactated % | 88.2 | 91.3 | 87.7 | 83.2 | 0.34 |
Mean age at menarche, years(SD) | 15.2± 1.7 | 15.5 ± 1.7 | 14.8 ± 1.7 | 14.8 ± 1.6 | 0.014 |
Lactation (yrs) median | 3.5 | 3.2 | 3.0 | 3.2 | 0.06 |
FSH | |||||
< 25.8 mIU/mL, % | 72 | 94 | 90 | 68 | < 0.0001 |
≥ 25.8 mIU/mL, % | 28 | 6 | 10 | 32 | |
Use of group method* | |||||
Median use last 5 yrs. (months) | 53 | 45 | 52 | NA | |
Median lifetime use (months) | 84 | 49 | 89 | NA | |
Median age at first use | 36 | 37 | 36 | NA | |
Radius BMD g/cm2 | 0.514 | 0.514 | 0.500 | 0.518 | 0.26 |