Table 2.
Reproductive health factors by ethnicity: All ethnicities (N=823)
| Bantu (N=661) |
Nilote (N=143) |
Cushite (N=19) |
Total (N=823) |
P values-All* | P values - Bantus and Nilotes only* | ||
|---|---|---|---|---|---|---|---|
| N (%) | N (%) | N (%) | N (%) | ||||
| Early menarche (<12) | 9 (1.4) | 0 (0) | 0 (0) | 9 (1.1) | |||
| Age at menarche | Normal menarche (12 - 14) | 305 (48.5) | 79 (56.0) | 9 (50.0) | 393 (49.9) | 0.40** | 0.12 |
| Late menarche (≥15) | 315 (50.1) | 62 (44.0) | 9 (50.0) | 386 (49.0) | |||
| Missing | 32 | 2 | 1 | 35 | |||
| Parity | Nulliparous | 28 (4.2) | 11 (7.7) | 3 (15.8) | 42 (5.1) | 0.03 | 0.10 |
| 1–2 children | 188 (28.4) | 32 (22.4) | 2 (10.5) | 222 (27.0) | |||
| >= 3 children | 445 (67.3) | 100 (69.9) | 14 (73.7) | 559 (67.9) | |||
| Missing | 0 | 0 | 0 | 0 | |||
| Age at first pregnancy | Nulligravid | 24 (3.7) | 9 (6.3) | 2 (10.5) | 35 (4.4) | 0.0008 | 0.0037 |
| <20 years | 154 (24.0) | 50 (35.0) | 10 (52.6) | 214 (26.6) | |||
| 20 - 29 years | 424 (65.9) | 71 (49.7) | 6 (31.6) | 501 (62.2) | |||
| >= 30 years | 41 (6.4) | 13 (9.1) | 1 (5.3) | 55 (6.8) | |||
| Missing | 18 | 0 | 0 | 18 | |||
| Cumulative breastfeeding | never breastfed | 28 (4.4) | 11 (8.0) | 3 (15.8) | 42 (5.3) | 0.08** | 0.15 |
| < 15 months | 29 (4.5) | 8 (5.8) | 0 (0) | 37 (4.6) | |||
| >= 15 months | 585 (91.1) | 118 (86.1) | 16 (84.2) | 719 (90.1) | |||
| Missing | 19 | 6 | 0 | 25 | |||
| Cumulative hormonal contraception exposure | < 48 months | 175 (44.0) | 32 (52.5) | 1 (33.3) | 208 (45.0) | 0.44** | 0.21 |
| = 48 months | 223 (56.0) | 29 (47.5) | 2 (66.7) | 254 (55.0) | |||
| Missing | 263 | 82 | 16 | 361 | |||
| Menopausal status | Premenopausal | 348 (52.7) | 64 (45.1) | 14 (73.7) | 426 (51.9) | 0.04 | 0.10 |
| Postmenopausal | 312 (47.3) | 78 (54.9) | 5 (26.3) | 395 (48.1) | |||
| Missing | 1 | 1 | 0 | 2 | |||
| Age at menopause† | < 50 years | 161 (62.2) | 29 (43.9) | 1 (20.0) | 191 (57.9) | 0.004** | 0.007 |
| ≥50 years | 98 (37.8) | 37 (56.1) | 4 (80.0) | 139 (42.1) | |||
| Missing | 53 | 12 | 0 | 65 | |||
| Family history of breast cancer in first degree female relative | No | 609 (92.1) | 133 (93.0) | 17 (89.5) | 759 (92.2) | 0.85 | 0.72 |
| Yes | 52 (7.9) | 10 (7.0) | 2 (10.5) | 64 (7.8) | |||
| Missing | 0 | 0 | 0 | 0 |
*
p-values from chi-square test except where noted; missing data were excluded from percentage calculations and statistical comparisons.
**
p-values from Fisher exact test.
†
Numbers are calculated for post-menopausal women only.