Table 2 Haemoglobin concentration and the risk of stillbirth
Cases | Controls | Odds Ratio (95 % Confidence Interval) | ||
|---|---|---|---|---|
n (%) | n (%) | Crude | Adjusteda | |
Haemoglobin concentration before pregnancy (g/l) | ||||
< 110 | 4 (2.5) | 31 (2.5) | 1.04 (0.36–3.04) | 1.23 (0.39–3.84) |
110–120 | 72 (45.6) | 582 (47.5) | Reference | Reference |
121–139 | 49 (31.0) | 360 (29.4) | 1.10 (0.75–1.61) | 0.97 (0.64–1.47) |
≥ 140 | 33 (20.9) | 252 (21.0) | 1.06 (0.68–1.64) | 0.83 (0.52–1.34) |
Continuous | 158 (100) | 1,225 (100) | 1.00 (0.99–1.02) | 1.00 (0.98–1.01) |
Haemoglobin concentration at first trimester (g/l) (gestational age weeks between 6 to 10) | ||||
< 110 | 26 (5.3) | 181 (6.5) | 0.91 (0.59–1.40) | 0.87 (0.55–1.37) |
110–120 | 223 (46.1) | 1,411 (50.5) | Reference | Reference |
121–139 | 152 (31.4) | 834 (30.0) | 1.45 (0.92–1.44) | 1.18 (0.94–1.49) |
≥ 140 | 83 (17.1) | 366 (13.1) | 1.43 (1.09–1.89) | 1.36 (1.01–1.81) |
Continuous | 484 (100) | 2,792 (100) | 1.01 (1.00–1.02) | 1.01 (1.00–1.02) |
Haemoglobin concentration at end of second trimester(g/l) (gestational age weeks between 26 to 30) | ||||
< 110 | 37 (14.0) | 523 (21.2) | 0.64 (0.44–0.92) | 0.63 (0.43–0.92) |
110–120 | 180 (65.2) | 1,618 (65.6) | Reference | Reference |
121–139 | 40 (14.4) | 268 (10.9) | 1.34 (0.93–1.93) | 1.19 (0.81–1.74) |
≥ 140 | 18 (6.4) | 59 (2.4) | 2.74 (1.58–4.75) | 2.31 (1.30–4.10) |
Continuous | 275 (100) | 2,468 (100) | 1.03 (1.02–1.04) | 1.03 (1.01–1.04) |