Interpreting Investigations in Pregnancy
| Investigations | Normal values | |
|---|---|---|
| Pregnant | Non-pregnant | |
| Haemoglobin g/dL | 105–140 | 120–150 |
| White cell count ×109/l | 6–16 | 4–11 |
| Platelets ×109/l | 150–400* | 150–400 |
| Haematocrit | 0.3–0.4 | 0.36–0.47 |
| MCV fL | 80–100 | 80–100 |
| Sodium mmol/l | 130–140 | 135–145 |
| Potassium mmol/l | 3.3–4.1 | 3.5–5.0 |
| Urea mmol/l | 2.4–4.1 | 2.5–7.5 |
| Creatinineμmol/l | 44–73 | 65–101 |
| Bicarbonate mmol/l | 18–22 | 22–28 |
| C-reactive protein (CRP) g/l | 0–7 | 0–7 |
| ESR | Unreliable – high | 0–10 |
| D-dimer mg/L | Unreliable – high† | <0.5 |
| pH | 7.35–7.45 | 7.40–7.48 |
| PaCO2 kPa/mmHg | 3.6–4.3/27–32 | 4.7–6.0/35–45 |
| PaO2 kPa/mmHg | 12.6–14.0/94–105 | 10.6–14.0/80–105 |
| Base excess | +2–2 | +2–2 |
| Peak expiratory flow (PEF) | No change | |
| Forced expiratory volume in 1 second (FEV1) | No change | |
* A 10% fall in platelet count maybe expected during pregnancy.