Comparison of maternal and infant characteristics across the exposure groups
| Maternal anaemia | |||
|---|---|---|---|
| Characteristics (N=1007, except where specified) | Normal haemoglobin/mild, n=656 | Moderate, n=330 | Severe, n=21 |
| Frequency (%) | Frequency (%) | Frequency (%) | |
| Maternal age, years | |||
| <20 | 75 (11.4) | 29 (8.8) | 0 (0) |
| 20–25 | 394 (60.1) | 204 (61.8) | 13 (61.9) |
| 26–30 | 149 (22.7) | 78 (23.6) | 6 (28.6) |
| ≥30 | 37 (5.6) | 19 (5.8) | 2 (9.5) |
| Not known | 1 (0.2) | 0 (0) | 0 (0) |
| BMI in kg/m2 | |||
| Underweight | 120 (18.3) | 61 (18.5) | 2 (9.5) |
| Normal | 338 (51.5) | 172 (52.1) | 7 (33.3) |
| Overweight | 42 (6.4) | 21 (6.4) | 3 (14.3) |
| Obese | 11 (1.7) | 8 (2.4) | 0 (0) |
| Not known | 145 (22.1) | 68 (20.6) | 9 (42.9) |
| Pregnancy-related factors | |||
| Parity* | |||
| Nulliparous | 98 (14.9) | 36 (10.9) | 0 (0) |
| Multiparous | 274 (41.8) | 184 (55.8) | 19 (90.5) |
| Not known | 284 (43.3) | 110 (33.3) | 2 (9.5) |
| Previous caesarean sections (multiparous women, n=477) | |||
| No | 180 (65.7) | 132 (71.7) | 15 (78.9) |
| Yes | 52 (19.0) | 31 (16.9) | 3 (15.8) |
| Not known | 42 (15.3) | 21 (11.4) | 1 (5.3) |
| Previous pregnancy problems* | |||
| No | 267 (40.7) | 168 (50.9) | 11 (52.4) |
| Yes | 44 (6.7) | 20 (6.1) | 3 (14.3) |
| Not known | 345 (52.6) | 142 (43.0) | 7 (33.3) |
| Anaemia during previous pregnancy* | |||
| No | 203 (30.9) | 108 (32.7) | 3 (14.3) |
| Yes | 7 (1.1) | 22 (6.7) | 10 (47.6) |
| Not known | 446 (68.0) | 200 (60.6) | 8 (38.1) |
| Pre-existing medical problems | |||
| No | 637 (97.1) | 313 (94.8) | 19 (90.5) |
| Yes | 18 (2.7) | 17 (5.2) | 2 (9.5) |
| Not known | 1 (0.2) | 0 (0) | 0 (0) |
| Index pregnancy | |||
| Multiple pregnancy | |||
| No | 647 (98.6) | 321 (97.3) | 21 (100) |
| Yes | 9 (1.4) | 9 (2.7) | 0 (0) |
| Not known | 0 | 0 | 0 |
| Number of antenatal check-ups* | |||
| ≥4 | 335 (51.1) | 183 (55.5) | 9 (42.9) |
| At least 1 but <4 | 232 (35.4) | 96 (29.1) | 7 (33.3) |
| None | 46 (7.0) | 38 (11.5) | 5 (23.8) |
| Not known | 43 (6.5) | 13 (3.9) | 0 (0) |
| Received folic acid tablets | |||
| No | 160 (24.4) | 88 (26.7) | 9 (42.9) |
| Yes | 495 (75.4) | 242 (73.3) | 12 (57.1) |
| Not known | 1 (0.2) | 0 (0) | 0 (0) |
| Received any treatment (women diagnosed with anaemia, n=499)* | |||
| No | 155 (23.6) | 107 (32.4) | 3 (14.3) |
| Yes | 44 (6.7) | 81 (24.6) | 16 (76.2) |
| Not known | 457 (69.7) | 142 (43.0) | 2 (9.5) |
| Infection during pregnancy (malaria/UTI/helminthic infection)* | |||
| No | 602 (91.8) | 282 (85.5) | 10 (47.6) |
| Yes | 17 (2.6) | 13 (3.9) | 3 (14.3) |
| Not known | 37 (5.6) | 35 (10.6) | 8 (38.1) |
| Placental problems during index pregnancy | |||
| No | 646 (98.5) | 323 (97.9) | 21 (100) |
| Yes | 9 (1.4) | 7 (2.1) | 0 (0) |
| Not known | 1 (0.1) | 0 (0) | 0 (0) |
| Mode of delivery* | |||
| Spontaneous vaginal | 289 (44.1) | 202 (61.2) | 14 (66.7) |
| Ventouse | 6 (0.9) | 1 (0.3) | 0 (0) |
| Forceps | 12 (1.8) | 3 (0.9) | 1 (4.7) |
| Breech | 3 (0.5) | 1 (0.3) | 0 (0) |
| Elective caesarean section | 72 (11.0) | 31 (9.4) | 0 (0) |
| Emergency caesarean section | 273 (41.6) | 91 (27.6) | 6 (28.6) |
| Not known | 1 (0.1) | 1 (0.3) | 0 (0) |
| Delivery induced | |||
| No | 567 (86.4) | 287 (87.0) | 17 (81.0) |
| Yes | 60 (9.2) | 22 (6.7) | 3 (14.3) |
| Not known | 29 (4.4) | 21 (6.3) | 1 (4.7) |
| Sociodemographic factors | |||
| Caste/social class* | |||
| Schedule caste | 68 (10.4) | 26 (7.9) | 2 (9.5) |
| Schedule tribe | 81 (12.3) | 61 (18.5) | 6 (28.6) |
| Other backward classes | 75 (11.4) | 57 (17.3) | 6 (28.6) |
| General | 431 (65.7) | 186 (56.4) | 7 (33.3) |
| Not known | 1 (0.2) | 0 (0) | 0 (0) |
| Religion* | |||
| Hindu | 456 (69.5) | 236 (71.5) | 16 (76.2) |
| Muslim | 190 (28.9) | 66 (20.0) | 2 (9.5) |
| Others | 5 (0.8) | 8 (2.4) | 2 (9.5) |
| Not known | 5 (0.8) | 20 (6.1) | 1 (4.8) |
| Residence | |||
| Rural | 560 (85.3) | 282 (85.5) | 19 (90.5) |
| Urban | 95 (14.5) | 48 (14.5) | 2 (9.5) |
| Not known | 1 (0.2) | 0 (0) | 0 (0) |
| Belongs to BPL household* | |||
| No | 309 (47.1) | 132 (40.0) | 6 (28.6) |
| Yes | 286 (43.6) | 143 (43.3) | 12 (57.1) |
| Not known | 61 (9.3) | 55 (16.7) | 3 (14.3) |
| Husband in paid employment | |||
| Employed | 594 (90.6) | 300 (90.9) | 18 (85.7) |
| Unemployed | 14 (2.1) | 6 (1.8) | 0 (0) |
| Not known | 48 (7.3) | 24 (7.3) | 3 (14.3) |
| Women in paid employment* | |||
| No | 571 (87.0) | 263 (79.7) | 14 (66.7) |
| Yes | 33 (5.0) | 31 (9.4) | 6 (28.6) |
| Not known | 52 (7.9) | 36 (10.9) | 1 (4.7) |
| Husband tea garden worker* | |||
| No | 562 (85.7) | 261 (79.1) | 12 (57.1) |
| Yes | 46 (7.0) | 45 (13.6) | 6 (28.6) |
| Not known | 48 (7.3) | 24 (7.3) | 3 (14.3) |
*p<0.05 for χ2 test for difference in proportion.
BMI, body mass index; BPL, below poverty line; UTI, urinary tract infection.