Drug dosesFree in the app
Anti-D & thromboprophylaxis
RhD-negative women and LMWH doses.
Source: BSH · NICE NG126 (2026) · RCOG 2026 Calculator
Loading the calculator…
Anti-D
| <12 weeks | Not needed for miscarriage or ectopic (NICE 2026). |
|---|---|
| 12+0–19+6 | ≥250 IU IM within 72 h; no Kleihauer. |
| ≥20 weeks | ≥500 IU + Kleihauer; more if fetal bleed is large. |
| RAADP | 1500 IU at 28–30 weeks, or 500 IU at 28 and 34 weeks. |
| After birth | ≥500 IU + Kleihauer if baby RhD-positive. |
LMWH prophylaxis
| <100 kg | Enoxaparin 40 mg daily |
|---|---|
| 100–129 kg | 60 mg daily |
| 130–169 kg | 80 mg daily |
| ≥170 kg | 0.6 mg/kg/day |
Treatment dose: enoxaparin 1 mg/kg twice daily (booking weight) for rest of pregnancy and ≥6 weeks postnatal.
A summary for trained clinicians. Always check the full guideline, the patient in front of you and your hospital's protocol. Spotted an error? Tell us.