From: Associations between birthweight and preterm birth and the ages at menarche and menopause
 | Birth weight category β (SE) P |  | |||||
---|---|---|---|---|---|---|---|
< 6 lbs. N = 7,096 | 6 lbs.–7 lbs. 15 oz. N = 52,661 | 8 lbs.–9 lbs. 15 oz. N = 15,591 | ≥ 10 lbs. N = 2,680 | Global P | |||
Menarche-related | |||||||
 | Age at menarche |  |  |  |  |  | |
 |  | Unadjusted (n=77,720) | -0.041 (0.02) 0.03 | Ref | -0.023 (0.01) 0.09 | 0.023 (0.03) 0.42 | 0.049 |
 |  | Adj. for demographics (n=74,840) | -0.044 (0.02) 0.02 | Ref | 0.005 (0.01) 0.72 | 0.046 (0.03) 0.12 | < 0.0001 |
 |  | Adj. for demographic and lifestyle factors (n=65,447) | -0.047 (0.02) 0.02 | Ref | -0.003 (0.01) 0.82 | 0.032 (0.03) 0.31 | < 0.0001 |
 | Age at first regular period |  |  |  |  |  | |
 |  | Unadjusted (n=65,289) | -0.026 (0.03) 0.31 | Ref | -0.043 (0.02) 0.02 | -0.050 (0.04) 0.21 | 0.07 |
 |  | Adj. for demographics (n=62,910) | -0.016 (0.03) 0.54 | Ref | -0.017 (0.02) 0.36 | -0.011 (0.04) 0.79 | < 0.0001 |
 |  | Adj. for demographic and lifestyle factors (n=55,274) | -0.011 (0.03) 0.68 | Ref | -0.016 (0.02) 0.42 | -0.026 (0.04) 0.54 | < 0.0001 |
Reproductive window | |||||||
 | Reproductive window (years) |  |  |  |  |  | |
 |  | Unadjusted (n=54,348) | -0.455 (0.09) < 0.0001 | Ref | 0.058 (0.07) 0.37 | -0.409 (0.14) 0.004 | < 0.0001 |
 |  | Adj. for demographics (n=52,445) | -0.403 (0.09) < 0.0001 | Ref | 0.034 (0.07) 0.61 | -0.466 (0.14) 0.001 | < 0.0001 |
 |  | Adj. for demographic and lifestyle factors (n=46,036) | -0.287 (0.10) 0.004 | Ref | 0.029 (0.07) 0.67 | -0.283 (0.15) 0.06 | < 0.0001 |
Menopause-related | |||||||
 | Age at last regular period |  |  |  |  |  | |
 |  | Unadjusted (n=70,263) | -0.585 (0.09) < 0.0001 | Ref | 0.042 (0.06) 0.51 | -0.135 (0.14) 0.33 | < 0.0001 |
 |  | Adj. for demographics (n=67,805) | -0.528 (0.09) < 0.0001 | Ref | 0.036 (0.06) 0.57 | -0.217 (0.14) 0.12 | < 0.0001 |
 |  | Adj. for demographic and lifestyle factors (n=59,460) | -0.445 (0.09) < 0.0001 | Ref | 0.063 (0.07) 0.35 | -0.083 (0.15) 0.57 | < 0.0001 |
 | Age at last vaginal bleeding |  |  |  |  |  | |
 |  | Unadjusted (n=71,538) | -0.717 (0.10) < 0.0001 | Ref | 0.034 (0.07) 0.62 | -0.214 (0.15) 0.16 | < 0.0001 |
 |  | Adj. for demographics (n=69,009) | -0.631 (0.10) < 0.0001 | Ref | 0.027 (0.07) 0.70 | -0.311 (0.15) 0.04 | < 0.0001 |
 |  | Adj. for demographic and lifestyle factors (n=60,492) | -0.524 (0.10) < 0.0001 | Ref | 0.048 (0.07) 0.52 | -0.151 (0.16) 0.35 | < 0.0001 |
 | Age at natural menopause |  |  |  |  |  | |
 |  | Unadjusted (n=62,015) | -0.494 (0.08) < 0.0001 | Ref | 0.060 (0.06) 0.32 | -0.308 (0.13) 0.02 | < 0.0001 |
 |  | Adj. for demographics (n=59,822) | -0.450 (0.09) < 0.0001 | Ref | 0.060 (0.06) 0.32 | -0.342 (0.13) 0.01 | < 0.0001 |
 |  | Adj. for demographic and lifestyle factors (n=52,416) | -0.350 (0.09) < 0.0001 | Ref | 0.059 (0.06) 0.35 | -0.159 (0.14) 0.25 | < 0.0001 |
 | Age at natural menopause (conservative) |  |  |  |  | ||
 |  | Unadjusted (n=54,413) | -0.478 (0.09) < 0.0001 | Ref | 0.041 (0.06) 0.52 | -0.361 (0.14) 0.01 | < 0.0001 |
 |  | Adj. for demographics (n=52,506) | -0.432 (0.09) < 0.0001 | Ref | 0.043 (0.06) 0.50 | -0.391 (0.14) 0.01 | < 0.0001 |
 |  | Adj. for demographic and lifestyle factors (n=46,084) | -0.317 (0.10) 0.001 | Ref | 0.035 (0.07) 0.61 | -0.219 (0.15) 0.14 | < 0.0001 |