Table 2.
Parity as an independent risk factor for breast cancer in women with Li-Fraumeni syndrome due to known germline TP53 variants
| Parameter | Number of women without breast cancer |
Number of women with breast cancer |
Hazard Ratio |
95%CI | p-value |
|---|---|---|---|---|---|
| Effect of parity on breast cancer risk (all women) | |||||
| Nulliparous | 34 | 33 | - | ||
| Parous | 33 | 52 | 1.07 | (0.66, 1.77) | 0.8 |
| Effect of parity on breast cancer risk stratified by age at study entry | |||||
| ≤ 40 years | |||||
| Nulliparous | 43 | 30 | - | ||
| Parous | 43 | 34 | 1. 12 | (0.66,1.91) | 0.7 |
| >40 years | |||||
| Nulliparous | 4 | 3 | - | ||
| Parous | 21 | 11 | 0.85 | (0.24,3.07) | 0.8 |
| Number of live births | |||||
| Nulliparous | 37 | 30 | - | ||
| 1 | 5 | 13 | 1.23 | (0.69,2.19) | 0.5 |
| 2 | 16 | 32 | 1.13 | (0.61,2.09) | 0.7 |
| 3 | 5 | 6 | 0.82 | (0.31,2.20) | 0.7 |
| 4+ | 5 | 3 | 0.29 | (0.04,2.12) | 0.23 |
| Per live birth | 0.93 | (0.76,1.14) | 0.5 | ||
| Age at first live birth (years) | |||||
| Nulliparous | 33 | 33 | - | ||
| <25 | 23 | 16 | 0.71 | (0.38,1.41) | 0.29 |
| 25–29 | 7 | 21 | 1.44 | (0.83,2.97) | 0.26 |
| ≥30 | 5 | 14 | 2.14 | (1.1,5.24) | 0.05 |
Parous= at least one liveborn child