Antenatal & maternal medicineFree in the app
Red cell antibodies
When to refer an antibody-positive mother.
Source: RCOG GTG 65| Anti-D | Below 4 IU/ml low risk; 4–15 moderate (refer to fetal medicine); above 15 severe. |
|---|---|
| Anti-c | Refer above 7.5 IU/ml; above 20 high risk. |
| Anti-K (Kell) | Refer at any level — titres underestimate severity. Check the father’s Kell status. |
| Testing | Every 4 weeks to 28 weeks, then every 2 weeks. |
| Fetal anaemia | MCA peak systolic velocity above 1.5 MoM or hydrops: refer for intrauterine transfusion. |
| Fetal genotype | Cell-free fetal DNA for D, C, c, E, e and K. |
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.