Please help - has anyone ever had a blood test to see if they need anti-D after a knock?

[whysoserious]

Basically as the title says - have you ever had a knock/fall/trauma to abdomen, had a blood test to see if you need anti-D beforehand which found there were no antibodies present and therefore you didn't need it?

I had an incident with sharp braking and seatbelt across tummy yesterday. Wasn't hurt, had no bleeding, felt baby move etc. Phone up maternity unit explaining all this and they said should be fine and to relax and let them know whether I start getting cramps/bleeding etc.

However, I still feel really worried about it and am playing the incident over and over in my head. The trouble is I have already had anti-d several times in this pregnancy as I seem to be very clumsy and have had some bleeding. I don't want to have it for the 'sake of it' if I phone them back with my concerns.

The ideal would be if they could test my blood for antibodies beforehand and of none found then I can relax. If some found then I know I definitely need it (I think this is the most unlikely scenario but I just have that tiny seed of 'what if' doubt in my head if you know what I mean.)

Has anyone had this done rather than the hospital just going straight in with the injection before waiting for the results of blood tests? (in my experience so far they seem to do this Kleihauer test but never wait for the actual results.)

Thanks for your help and sorry for the waffle!

If you're worrying then go and see your gp or midwife and explain what happened, I'm sure it wouldn't be too difficult for them to do a quick blood test to check. It's not like you're asking for the anti d without knowing if it's necessary, sounds sensible to check first. How many weeks are you? Does your trust usually give it ante or postnatally?

thanks for your reply DrHamster.

I'm 24 weeks. My trust gives it both ante and postnatally (after a test to check the baby is not rhesus negative also.)

I have asked about a Kleihauer test before when I had anti-D before (only a couple of weeeks back) and they said i should just have the anti-D. I'm not comfortable with this again and would prefer to check IF i need it first of all. Mainly because I strongly suspect I don't but there's still that worry in my mind IYSWIM.

I'm sure I've heard people say on here they've had a knock/bump, went into hospital for a check up, had a blood test for antibodies and it showed no fetal bleeding therefore they didn't need the anti-D. This would be ideal for me.

bump.

anyone?

Hi whyso, I'm rhesus neg too - nightmare isn't it? One more thing to worry about! As far as I understand it, and I have had far more discussions about this with midwives/consultants than I'd have liked, for various reasons! - the blood test is to check that you have NO antibodies, because if you have them already there isn't any point giving anti-d.

The anti-d basically is ?'fake'/inactive? (I'm not really sure) antibodies that trick your body into thinking it has already produced them so doesn't need to produce more. That's how it prevents you from having a full-on immune response and becoming sensitised. I think!

I had a knock, and a blood test to check I had no antibodies before they would give me the anti-d.

The kleihauer test will detect the anti-d you've been given so it will show you have antibodies in any case - so wont be helpful, however if you've had anti-d two weeks ago this will protect you now, I would think. Did you have the injection in your arm or your bum? If your arm, it's a much stronger and longer lasting dose so I would think if you've just had a very minor knock you don't have anything to worry about.

I hope thats reassuring, hopefully someone who knows what they're talking about will be along to confirm whether I'm right!

No

I had a small bleed and had the anti d jab and the kleihauer blood test at the same time - i.e. they didn't wait for the blood test results before giving me the anti d. Just like your experience so far.

It may be a timing thing, because anti d has to be given within 72 hours to be effective, and maybe the blood test results were going to take longer than that. But then I am not really sure what the blood test is for tbh

I was told the jab would cover me for 2 weeks.

I am v confused. You posted yesterday too?

My understanding is that the anti d is for the whole pregnancy? That it protects you and future babies in event of there being bleeding with this one. I am not clear why you would need additional anti d if you've already had some? Although I understand that older versions only lasted for a limited time. But even if you are on the less hardcore version, I see no reason why you need more as a) you have had recently and b) a seatbelt problem at 24 weeks in unlikely to cause bleeding I think.

here is a link