Rh positive mummy with anti-c antibody...can anyone help advise me?

[peppapigisgreat]

Hello all, I am 16 weeks pregnant with my second child and was told at my 12 week scan that one of my blood tests came back positive for anti-c antibody. They also sent me a card stating my blood type which is B RHd positive. From reading everything I can find about rhesus etc, im starting to get confused because some sites say there isnt anything to worry about if the mother is Rh positive but then im now worried about what anti-c actually means and how it will affect my child...!? Also, if I am rhd positive and my baby is rhd negative, will that cause complications?? any help would be great!

It’s all super confusing. I’ll do my best to go through it for you. You can try having a read of the RCOG guideline (google RCOG red cell antibodies) which might help you.

Basically RH negative or positive only refers to the D antigen which is the most common. For you, it’s the c antigen which is the issue. So while you are RHD positive (and therefore wouldn’t need anti D injections) you are Rh - c negative. At some point, probably the last oregnancy, your body has encountered some c type antigen, and because you are c negative and don’t have that antigen, your body has reacted by creating c antibodies. They now are able to circulate in your body, and can cross the placenta. Whether or not that is a problem for your pregnancy/newborn depends on two things - one is how much antibody you have (the titre), but more important is what c type your baby has.

If your baby is c negative, then there is no concern. If your baby is c positive, then your antibodies can recognise and attack the baby’s c antigen and destroy those red cells, leading to anaemia.
It’s not common for that to happen - but it is something to watch for.

I believe the NHS is now doing NIPT (a blood test for you) to identify baby’s blood group and therefore decide how to manage pregnancies with blood group antibodies. Im just not sure whether they like to do the NIPT for everyone in your situation or whether they check the antibody levels/titres first and only do th NIPT it the levels rise.

Basically, I think you need a referral to an obstetrician to discuss all this, and then there will be a set management protocol.
If you are able to have the NIPT and baby is c negative then you would just be back to normal. If baby is c positive then you’ll likely need antibody titres done, and if the titres (levels) become high then you get scans to check on baby every couple of weeks. Most of the time everything stays totally fine. Even if the scans show concerns then there are treatments available.

Hope that helps?
The referral should happen soon as well - it’s something that needs to be sorted for you in the next few weeks rather than waiting until third trimester for example.

Thank you so much! This has been a lot more helpful than the majority of the info on the net!

I guess all this time i was reading and worrying about rhesus disease and whether me being rh positive meant the same as the articles I've read, but now the question is what affect the anti c antibody may have (may not have) on my baby, i can't seem to find anything on this.

I'll try to speak to someone at my hospital for more advice but from what I've experienced so far, they're very neutral in their opinions.

It’s totally possible they’re neutral/not that fussed because there’s no reason to be - your antibody titre may well already be on the blood test report, and if it’s a low titre then there’s usually no major issue. Where I am we don’t have the NIPT routinely yet so we just monitor the titre and we only worry if the titre rises. But either way it would be nice if someone would discuss withyou!!

Also, worth mentioning that they've already told me that my first blood test showed very low traces of anti-c but i've seen articles where the levels fluctuate a lot and often increase towards the due date.

I've been told that they'll be doing blood tests every 4 weeks up to 28 weeks and then it'll be every 2 weeks.

I've not heard of the NIPT test so may be they'll bring this up next time, if not i'll mention it!

Ah so maybe it’s the same where you are - the NIPT for this is quite a new technology. Sounds like you actually have a good plan in place, just were missing out the explanation! Hope all a little clearer now.

Yes, thank you so much! Hope it all remains calm and this one comes out without any complications!