If you are rhesus negative and your husband is rhesus positive, then your unborn child may inherit negative or positive blood – you wont know until birth.
However if the mother is negative and the foetus happens to be positive (positive being dominant, negative recessive), this may cause problems for the foetus as well as any future pregnancies the mother may have.
Problems can occur if the foetus’ positive blood manages to find it’s way into the mother’s bloodstream, either during pregnancy or labour, mixing with her negative blood.
If this happens and it is not treated, the mother’s blood can create antibodies to attack the positive blood containing a ‘foreign’ component, causing anaemeia or in a worst case scenario, death for a foetus.
This means that any future pregnancies the mother has where the foetus is again rhesus positive, her antibodies may cross the placenta and attack the foetus’ blood cells.