The association between stillbirth and socioeconomic behavioural and biodemographic factors: frequencies, unadjusted and adjusted ORs
| Variables | Total births N=886 505 Frequency (%) | Stillbirths N=8429 Frequency (%) | Live births N=878 076 Frequency (%) | Unadjusted OR (95% CI*) | Adjusted OR† (95% CI*) |
| Maternal age (years) | |||||
| 15–19 | 33 482 (3.7) | 436 (4.9) | 33 046 (3.7) | 1.52 (135 to 1.72) | 1.76 (1.55 to 2.00) |
| 20–24 | 324 130 (36.0) | 3079 (36.2) | 321 051 (36.0) | 1.17 (1.09 to 1.24) | 1.29 (1.21 to 1.37) |
| 25–29 | 301 330 (33.7) | 2546 (29.2) | 298 784 (33.7) | 1.00 (Ref) | 1.00 (Ref) |
| 30–34 | 143 529 (16.6) | 1400 (17.1) | 142 129 (16.6) | 1.20 (1.11 to 1.29) | 1.05 (0.97 to 1.14) |
| 35–39 | 55 893 (6.6) | 643 (8.2) | 55 250 (6.6) | 1.43 (1.29 to 1.59) | 1.16 (1.04 to 1.29) |
| 40–45 | 20 006 (2.4) | 244 (3.4) | 19 762 (2.4) | 1.63 (1.39 to 1.91) | 1.29 (1.09 to 1.51) |
| 45–49 | 8135 (1.0) | 81 (1.1) | 8054 (1.0) | 1.24 (0.96 to 1.60) | 1.04 (0.80 to 1.35) |
| Place of residence | |||||
| Urban | 123 099 (16.4) | 874 (12.7) | 122 225 (16.4) | 1.00 (Ref) | 1.00 (Ref) |
| Rural | 763 406 (83.7) | 7555 (87.4) | 755 851 (83.6) | 1.35 (1.24 to 1.47) | 1.27 (1.16 to 1.39) |
| Religion | |||||
| Hindu | 734 134 (81.5) | 6522 (75.3) | 727 612 (81.5) | 1.00 (Ref) | 1.00 (Ref) |
| Muslim | 125 723 (15.9) | 1619 (21.6) | 124 104 (15.8) | 1.48 (1.39 to 1.58) | 1.33 (1.25 to 1.43) |
| Christian | 14 914 (1.8) | 178 (2.4) | 14 736 (1.8) | 1.49 (1.25 to 1.78) | 1.42 (1.19 to 1.70) |
| Others | 11 734 (0.9) | 110 (0.7) | 11 624 (0.9) | 0.87 (0.69 to 1.11) | 1.06 (0.84 to 1.35) |
| Social group | |||||
| Other | 598 477 (68.4) | 5868 (70.0) | 592 609 (68.4) | 1.00 (Ref) | 1.00 (Ref) |
| Schedule caste | 161 273 (19.2) | 1644 (21.4) | 159 629 (19.2) | 1.09 (1.02 to 1.16) | 1.11 (1.04 to 1.19) |
| Schedule tribe | 126 755 (12.4) | 917 (8.7) | 125 838 (12.5) | 0.68 (0.62 to 0.74) | 0.74 (0.68 to 0.81) |
| Maternal education | |||||
| Tertiary and above | 36 617 (3.9) | 188 (2.2) | 36 429 (4.0) | 1.00 (Ref) | 1.00 (Ref) |
| Secondary | 110 458 (11.3) | 786 (8.2) | 109 672 (11.3) | 1.31 (1.08 to 1.60) | 1.10 (0.90 to 1.34) |
| Primary and below | 364 809 (39.1) | 3413 (38.1) | 361 396 (39.1) | 1.77 (1.48 to 2.12) | 1.34 (1.10 to 1.62) |
| Illiterate | 374 621 (45.7) | 4042 (51.6) | 370 579 (45.6) | 2.06 (1.72 to 2.47) | 1.43 (1.17 to 1.74) |
| Employment | |||||
| In paid employment | 154 177 (16.4) | 1273 (13.2) | 152 904 (16.4) | 1.00 (Ref) | 1.00 (Ref) |
| Not in-paid employment | 732 328 (83.6) | 7156 (86.8) | 725 172 (83.6) | 1.29 (1.20 to 1.38) | 1.15 (1.07 to 1.24) |
| Asset index, quintiles | |||||
| 5=‘Highest’ | 159 957 (17.9) | 1133 (13.6) | 158 824 (17.9) | 1.00 (Ref) | 1.00 (Ref) |
| 4 | 160 335 (17.6) | 1422 (16.9) | 158 913 (17.6) | 1.26 (1.14-1.38) | 1.34 (1.01 to 1.79) |
| 3 | 159 567 (18.0) | 1606 (19.3) | 157 961 (18.0) | 1.41 (1.29 to 1.55) | 1.91 (1.45 to 2.52) |
| 2 | 157 506 (17.9) | 1654 (19.8) | 155 852 (17.8) | 1.46 (1.33 to 1.60) | 2.45 (1.85 to 3.24) |
| 1=‘Lowest’ | 155 283 (18.0) | 1626 (18.9) | 153 657 (17.9) | 1.39 (1.26 to 1.52) | 2.42 (1.82 to 3.21) |
| Missing | 93 857 (10.7) | 988 (11.5) | 92 869 (10.7) | 1.41 (1.27 to 1.56) | 1.21 (0.91 to 1.62) |
| Current smoking‡ | |||||
| No | 725 560 (82.0) | 6670 (79.6) | 718 890 (82.0) | 1.00 (Ref) | – |
| Yes | 6553 (0.8) | 80 (1.2) | 6473 (0.8) | 1.53 (1.19 to 1.97) | – |
| Missing | 154 392 (17.2) | 1679(19.3) | 152 713 (17.2) | 1.16 (1.08 to 1.23) | – |
| Chewing tobacco‡ | |||||
| No | 635 393 (74.1) | 5743 (71.5) | 629 650 (74.1) | 1.00 (Ref) | 1.00 (Ref) |
| Yes | 96 806 (8.7) | 1010 (9.3) | 95 796 (8.7) | 1.10 (1.01 to 1.19) | 1.11 (1.02 to 1.21) |
| Missing | 154 306 (17.2) | 1676 (19.2) | 152 630 (17.2) | 1.16 (1.09 to 1.24) | 1.44 (1.29 to 1.59) |
Frequencies are true counts, % and OR are weighted for design effects and non-response.
*The 95 % CIs were calculated using linearised SEs.
†Multivariable logistic regression, adjusting for the other variables in the model, except self-reported mental illness. The model also adjusts for the observed significant interaction between gravidity and asset index. Smoking was not significantly associated with stillbirth during the model-building process and therefore removed from the final model.
‡These variables reflect practice at the time of the survey.