Table 5. Multinomial logistic regression- significant adjusted OR of characteristics and their association with age at natural menopause.
| Characteristics | Age at natural menopause (years) | |||
|---|---|---|---|---|
| ≤40 OR(95% CI) | 41–44 OR(95% CI) | 45–49 OR(95% CI) | ≥ 53 OR(95% CI) | |
| Socio-demographic | ||||
| Age (years) | ||||
| ≤50 | 4.38(2.88–6.68) | 5.81(4.12–8.19) | 5.86(4.59–7.50) | 0.03(0.004–0.20) |
| 51–55 | 0.20(0.14–0.27) | 0.45(0.36–0.57) | 0.66(0.58–0.75) | 0.68(0.56–0.82) |
| 56–60 | 0.36(0.28–0.48) | 0.62(0.50–0.77) | 0.78(0.70–0.88) | 1.65(1.40–1.94) |
| 61–65 | 0.52(0.40–0.69) | 0.81(0.66–1.01) | 0.87(0.77–0.98) | 1.38(1.16–1.64) |
| >65 | Ref. | Ref. | Ref. | Ref. |
| Highest education | ||||
| No formal school | Ref. | Ref. | Ref. | Ref. |
| Primary school | 0.74(0.59–0.94) | 0.81(0.69–0.96) | 0.88(0.81–0.96) | 1.20(1.07–1.35) |
| Middle school | 0.98(0.56–1.70) | 1.13(0.79–1.63) | 0.96(0.77–1.18) | 1.80(1.38–2.34) |
| High school or above | 1.35(0.47–3.91) | 1.59(0.81–3.14) | 1.01(0.65–1.57) | 2.26(1.34–3.83) |
| Lifestyle | ||||
| Smoking status | ||||
| Never | Ref. | Ref. | Ref. | Ref. |
| Occasional | 0.52(0.22–1.20) | 0.62(0.34–1.15) | 0.89(0.67–1.17) | 0.52(0.34–0.82) |
| current regular | 1.46(0.89–2.41) | 1.80(1.22–2.65) | 1.21(0.94–1.56) | 0.67(0.45–1.00) |
| Body mass index | ||||
| Underweight | 1.20(0.90–1.62) | 1.55(1.25–1.93) | 1.37(1.20–1.56) | 0.75(0.61–0.92) |
| Normal weight | Ref. | Ref. | Ref. | Ref. |
| Overweight | 0.85(0.69–1.05) | 0.94(0.81–1.09) | 0.93(0.85–1.00) | 1.04(0.93–1.16) |
| Obesity | 0.70(0.47–1.03) | 0.84(0.64–1.09) | 0.84(0.73–0.97) | 1.08(0.90–1.30) |
| Physical activity | ||||
| Low | Ref. | Ref. | Ref. | Ref. |
| Middle | 1.10(0.89–1.36) | 1.20(1.02–1.42) | 0.95(0.87–1.04) | 1.15(1.00–1.32) |
| High | 1.12(0.87–1.45) | 1.30(1.07–1.57) | 0.89(0.81–0.99) | 1.13(0.97–1.30) |
| Dietary | ||||
| Meat | ||||
| <1 day per week | Ref. | Ref. | Ref. | Ref. |
| 1–3 days per week | 0.93(0.72–1.20) | 0.95(0.78–1.16) | 1.10(0.98–1.23) | 1.27(1.08–1.49) |
| ≥4 days per week | 0.85(0.65–1.13) | 0.91(0.74–1.12) | 0.99(0.88–1.12) | 1.18(1.00–1.40) |
| Sea food | ||||
| <1 day per week | Ref. | Ref. | Ref. | Ref. |
| 1–3 days per week | 0.94(0.78–1.14) | 0.83(0.72–0.95) | 0.84(0.78–0.91) | 1.03(0.93–1.15) |
| ≥4 days per week | 0.95(0.51–1.79) | 1.07(0.71–1.60) | 0.92(0.73–1.16) | 0.91(0.65–1.27) |
| Fresh eggs | ||||
| <1 day per week | Ref. | Ref. | Ref. | Ref. |
| 1–3 days per week | 1.13(0.94–1.36) | 0.87(0.76–1.00) | 0.96(0.89–1.04) | 0.94(0.85–1.05) |
| ≥4 days per week | 0.78(0.52–1.15) | 0.74(0.56–0.96) | 0.72(0.62–0.83) | 0.80(0.66–0.98) |
| Fresh fruits | ||||
| <1 day per week | Ref. | Ref. | Ref. | Ref. |
| 1–3 days per week | 0.60(0.49–0.73) | 0.69(0.59–0.79) | 0.90(0.83–0.97) | 0.94(0.84–1.05) |
| ≥4 days per week | 0.54(0.40–0.73) | 0.73(0.60–0.90) | 0.90(0.81–1.01) | 1.05(0.90–1.22) |
| Vitamins intake | ||||
| Yes | 0.54(0.35–0.84) | 1.19(0.95–1.50) | 0.94(0.82–1.07) | 1.09(0.92–1.30) |
| No | Ref. | Ref. | Ref. | Ref. |
| Experienced severe food shortage | ||||
| Yes | 0.80(0.65–0.97) | 0.82(0.71–0.95) | 0.83(0.76–0.89) | 1.09(0.97–1.22) |
| No | Ref. | Ref. | Ref. | Ref. |
| Reproductive | ||||
| Age at menarche (years) | ||||
| ≤12 | 2.14(1.36–3.36) | 1.59(1.09–2.30) | 0.85(0.66–1.08) | 0.85(0.60–1.22) |
| 13–14 | 0.95(0.71–1.28) | 1.44(1.18–1.75) | 1.08(0.97–1.22) | 0.93(0.79–1.10) |
| 15 | Ref. | Ref. | Ref. | Ref. |
| 16 | 0.74(0.56–0.97) | 0.86(0.70–1.04) | 0.96(0.87–1.07) | 1.07(0.92–1.23) |
| ≥17 | 0.96(0.76–1.21) | 0.86(0.71–1.02) | 1.01(0.92–1.11) | 1.12(0.98–1.28) |
| Number of live births | ||||
| ≤1 | Ref. | Ref. | Ref. | Ref. |
| 2 | 0.49(0.34–0.68) | 0.64(0.49–0.84) | 0.84(0.71–0.98) | 1.95(1.48–2.58) |
| ≥3 | 0.38(0.28–0.53) | 0.54(0.43–0.69) | 0.69(0.60–0.80) | 1.63(1.25–2.13) |
| Age at first birth (years) | ||||
| <20 | Ref. | Ref. | Ref. | Ref. |
| 20–24 | 1.23(1.02–1.50) | 1.07(0.93–1.23) | 1.10(1.02–1.19) | 0.96(0.87–1.07) |
| 25–29 | 1.33(0.93–1.91) | 1.01(0.77–1.33) | 1.11(0.96–1.28) | 0.75(0.60–0.94) |
| ≥30 | 1.39(0.60–3.21) | 0.42(0.16–1.07) | 0.89(0.61–1.29) | 0.83(0.48–1.45) |
Bold values represent significant results.
Ref.: reference group, OR: odds ratio, CI: confidence interval.