Table 3.
Multiple cox proportional hazard models of relationship between timing of first childbirth and background characteristics
| Model I | Model II | Model III | Model IV | |
|---|---|---|---|---|
| Characteristics | aHR(95 % CI) | aHR(95 % CI) | aHR(95 % CI) | aHR(95 % CI) |
| Residence | ||||
| North Central | *0.89(0.84–0.94) | 0.96(0.91–1.02) | 0.99(0.94–1.05) | |
| North East | *1.14(1.07–1.21) | *1.16(1.09–1.23) | *1.20(1.13–1.28) | |
| North West | *1.21(1.13–1.29) | *1.22(1.14–1.31) | *1.26(1.18–1.35) | |
| South East | 1.00(0.91–1.09) | 0.95(0.87–1.03) | 0.98(0.90–1.07) | |
| South South | *0.94(0.88–1.00) | 1.03(0.97–1.09) | 1.02(0.96–1.08) | |
| South Westa | ||||
| Residence | ||||
| Urbana | ||||
| Rural | *1.42(1.38–1.46) | *1.14(1.11–1.17) | *1.15(1.12–1.19) | |
| Education | ||||
| No education | *3.97(3.77–4.17) | *3.17(3.00–3.36) | *3.36(3.17–3.55) | |
| Primary | *3.39(3.22–3.57) | *3.12(2.96–3.29) | *3.24(3.08–3.42) | |
| Secondary | *1.83(1.74–1.92) | *1.75(1.67–1.84) | *1.79(1.71–1.88) | |
| Highera | ||||
| Age at 1st Marriage | ||||
| Nevera | *0.16(0.14–0.19) | *0.19(0.18–0.20) | ||
| Before 15 | *5.92(5.57–6.01) | *6.31(5.92–6.56) | ||
| 15–19 | *3.00(2.89–3.10) | *3.02(2.92–3.13) | ||
| 20+ | ||||
| Religion | ||||
| Catholicsa | ||||
| Other Christian | *1.07(1.02–1.12) | *1.07(1.02–1.12) | *1.08(1.03–1.13) | |
| Islam | *1.43(1.35–1.51) | *1.12(1.06–1.19) | *1.16(1.10–1.23) | |
| Others | *1.54(1.39–1.71) | *1.16(1.05–1.29) | *1.21(1.09–1.35) | |
| Ethnicity | ||||
| Yorubaa | ||||
| Igbo/Ibiobio | *0.86(0.80–0.94) | *0.83(0.77–0.91) | *0.85(0.78–0.93) | |
| Hausa/Fulani | *1.37(1.28–1.46) | *1.11(1.04–1.18) | *1.16(1.09–1.24) | |
| Others | *1.18(1.11–1.24) | 0.99(0.93–1.04) | 1.02(0.96–1.08) | |
| Ever Had pregnancy terminated | ||||
| Noa | ||||
| Yes | *1.09(1.05–1.13) | |||
| Ever used contraceptives | ||||
| No | *0.79(0.76–0.81) | |||
| Yesa | ||||
| Region | ||||
| Southa | ||||
| North | *1.24(1.20–1.27) | |||
| −2Log L | 526,294.41 | 528,314.50 | 525,688.86 | 525,434.08 |
| Chi Square | 7029.51 | 5009.11 | 7634.74 | 7889.53 |
aHR adjusted Hazard ratio CI Confidence Interval a Reference *Significant at p < 0.05