Choosing a Sperm Donor: Why Rhesus (Rh) Status Matters – Especially for Rh-Negative patients

When choosing a sperm donor, clients often consider a range of factors, such as: 

·         Physical characteristics

·         Medical history

·         Education level

·         Ethnicity

·         Personal interests

·         Blood type - including Rhesus (Rh) factor

Whilst many of these factors are personal preferences, Rh status is a medically important factor to consider, especially for women who are Rh-negative. Understanding the significance of Rh factor can help you make informed decisions and feel more confident throughout your fertility journey.

What is Rh factor?

Rh factor is a protein on the surface of red blood cells. If you have the protein you are Rh-positive; if you don’t have it, you are Rh-negative. Rh factor is entirely genetic and can be tested by taking a blood test. Whilst your Rh factor doesn’t affect your day-to-day health, it can play a significant role during pregnancy.

Did you know: 85% of people in the UK are Rh-positive.

Why Rh factor matters in donor selection

If a Rh-negative mother conceives a baby with an Rh-positive donor, the baby has a 50% chance of being Rh-positive and a 50% chance of being Rh-negative. If the baby is Rh-negative it is not at risk. However, if the mother is Rh-negative and the baby is Rh-positive, this is called 'Rh incompatibility'.

 How Rh incompatibility occurs: 

1. During pregnancy or childbirth, some of the baby’s Rh-positive blood may mix with the mother's Rh-negative blood. This is known as 'sensitisation'.

2. The mother’s immune system will recognise the blood cells from the baby as foreign. This leads to the development of Rh antibodies against those blood cells.

3. This is generally harmless in the first pregnancy, as the antibodies take time to form. However, for future pregnancies, with another Rh-positive baby, the antibodies can cross the placenta and attack the baby's red blood cells. This causes Rh disease.

4. Rh disease involves an immune attack, that can cause serious complications, including haemolytic anaemia, jaundice, organ damage and in severe cases, stillbirth. 

Whilst Rh factor does not affect the health of the mother, it can be life-threatening to the baby.

When is the baby at risk?

Note: Rh compatibility is only a concern if the mother is Rh-negative and the donor is Rh-positive.

Should you always match Rh status?

Not necessarily. Rhesus disease can be prevented by selecting a donor that has the same Rhesus status as you (if you are Rh-negative), especially if you are planning to have more than one child. This eliminates the chances of Rh incompatibility. However Rh incompatibility can be treated by taking Rho (D) immunoglobulin (also known as 'anti-D'). This injection prevents the body from making any Rh antibodies, which could cause serious health problems to the baby or affect any future pregnancies. This treatment option is mostly safe but requires constant monitoring and is only effective if your body hasn’t already made Rh antibodies.

If you are planning to conceive using donor sperm and you are Rh negative, understanding the implications of Rh factor is essential. Whilst modern medicine has made Rh disease rare, and almost always treatable, being informed of your Rh status gives you more control of your fertility journey.

#Femalefertility #DonorSperm #DonorInsemination #PregnancyJourney #RhesusStatus

Blog written by Monica Patel