Screening for sickle cell and beta thalassaemia
Carrier screening during pregnancy
Many of the people we talked to discovered they were a carrier of sickle cell or beta thalassaemia during pregnancy. The NHS Screening Programme has been introducing a programme of antenatal screening for these conditions. All women are now offered screening for beta thalassaemia as part of their routine antenatal tests. Those at high risk of being a sickle cell carrier will also be offered a screening test. Ideally, these tests should be done before 10 weeks of pregnancy.
“All pregnant women are offered a test for thalassaemia but not all women are automatically offered a test for sickle cell disease. The screening offered depends on where you live. In areas where haemoglobin diseases are more common, you will be offered a blood test for sickle cell disease. In areas where haemoglobin diseases are less common, a questionnaire is used to identify the baby’s mother and father’s family origins. If the questionnaire shows either parent may be a sickle cell carrier, a screening test is offered to the woman. You can ask to have the test even if your family origins do not suggest the baby would have a high chance of a haemoglobin disease.” (Screening tests for you and your baby – Public Health England July 2017)
If the test is positive the baby's father will also be offered a test.
The blood tests involve taking a blood sample which is then sent to the laboratory to be analysed. For most people the result shows that they are not carriers (this is also known as a 'negative' result), but a few will get a letter or phone call to tell them that they are a carrier of sickle cell or beta thalassaemia (which is called a 'positive' result). In some cases they may be told they carry another type of haemoglobin (or 'haemoglobin variant'), such as haemoglobin C, E, D or O Arab.
Some people we talked to saw screening as just another routine blood test in pregnancy and did not expect any bad news. Several felt they had not been fully informed or sufficiently prepared for the consequences of a 'positive' test result. A few people believed it was the law that they had to have the test, although in fact everyone has a right to say they don't want to be screened. Although it was clear some people we talked to had not been well informed about screening and carrier status, the NHS Screening Committee is working to ensure that in future everyone receives clear and consistent information and advice before and after screening and had produced a booklet ‘Screening tests for you and your baby’ that should be given to all pregnant women by their midwife or GP.This includes information about screening for sickle cell and thalassaemia in early pregnancy.
She did not realise she was being screened for beta thalassaemia, so was shocked to learn she was a carrier.
She did not realise she was being screened for beta thalassaemia, so was shocked to learn she was a carrier.
So did, when they took all these blood tests, did you know what any of them were for?
No, they just took them. They didn't say, they just wanted to check I think the iron levels and things like that, and that's how it came about. But they did take more blood than usual on one occasion. I didn't know why, but they just had to check everything, but it was alright.
Have you ever looked back over any of the stuff in your notes, did it say anywhere in the written information this is what they were doing, as far as you know?
No [pause] no.
So this was a complete out of the blue shock?
Yeah, definitely.
And did you know anything about thalassaemia?
A little bit, because they do put a little booklet in about it, but you know they don't exactly tell you you're going to be tested for it. As far as I was aware, anyway.
His partner and he had screening in pregnancy because they thought it was routine and just something everyone did.
His partner and he had screening in pregnancy because they thought it was routine and just something everyone did.
I'm interested in sort of what made you both willing to have screening in the first place. Was it something you hadn't thought about at all and it just seemed like everybody did it?
Well, I know that is the norm in this country, that once you are pregnant, all pregnant women have to take the screening. So, well, when her GP actually said she was going to take the test this day or that day, I didn't think of even saying, 'Oh no, don't go.' It's, I think it's I took it as normal, you know, a normal thing. So I never thought of not going. Never. Yeah. I never thought of it. I think it's a normal, normal thing. But to tell me to go for the screening without the pregnancy, then I don't think I would have gone, because I always think I'm strong, I'm not sick. I don't even know my GP, after four years of being in this country. I've got a GP. I know his name, but I haven't seen him personally, because I hardly fall sick. I'm always there. So to tell me, 'Go and take the tests', I don't think I would have gone. But because of the pregnancy, I know it's a general phenomenon, so she has to go, and that's it.
Did she ever think of saying no, or -?
No, she didn't. She didn't, because she just went, yeah.
So that was the main thing that made you both - it was just the fact that it was a normal part of care?
Yeah.
Footnote - often people do not realise that being a carrier does not affect your general health and you may have no idea you are a carrier unless you are tested.
Even though they had a leaflet about the carrier screening test, they never believed they could be affected.
Even though they had a leaflet about the carrier screening test, they never believed they could be affected.
Were you aware when you had all the routine blood tests that this was one of the things being tested for?
Father' No. Well, there was a leaflet, but it just never - no one, I don't know anybody who's gone through it, do you know what I mean? And there's nobody I know who had this sort of problem. So I just, I mean in the pack there's so many - there was a leaflet but I just didn't take it seriously. I didn't understand. 'It couldn't happen to us' you know what I mean? Because we don't smoke, we don't drink, so, you know, we live a very healthy lifestyle. So you just can't think, 'It couldn't really happen.' So yeah, the implication of it all didn't really, didn't really hit us at all.
Was that true of screening for other things as well, I mean, like Down's syndrome?
Father' Down's we understand, because Down's we can see and we've seen it in other people, so we understand that. But this thing is just completely - and the thing is I think the most traumatic aspect is that we're born with it. It's not something that we, not because of our lifestyle, but it's because we're born with it. And we thought, you know, we might be a bit unlucky really to, for both of us to have it, really. And it's strange really, because within the Vietnamese community in [city] people were having children without a problem at all. And we felt a bit weird really that we had this problem.
Footnote - often people do not realise that being a carrier does not affect your general health and you may have no idea you are a carrier unless you are tested.
Most people we talked to who were screened in pregnancy said that they were offered the test automatically (or did not realise they were having it), but a few were screened at their own request.
She asked to have carrier screening in pregnancy because of a family history of sickle cell.
She asked to have carrier screening in pregnancy because of a family history of sickle cell.
You know that I had the sickle trait only, so I only have it from one side of, from one of my parents. And in fact I hadn't been offered the screening during my first pregnancy. I was told I would have some blood tests and knowing that my family in Senegal has, that there is sickle cell, I was curious. So I asked if I, if they could do the screening at the same time. And then I asked for my daughter when she was born, and they found that she had the sickle cell trait as well. So I just asked for it and got the results, together with the results of the first blood tests that they did for pregnancy.
Hmm. So were you kind of expecting to find out you were a carrier then?
Yes, I did, yeah. I didn't know about my daughter, but I was expecting, because I have a half brother who has, who is a carrier. We have the same father, so I wasn't surprised.
Mmm. You were never tested as a child?
No.
He knew from childhood that he was a beta thalassaemia carrier, and suggested his partner should be tested during pregnancy, but they never expected her to be a carrier.
He knew from childhood that he was a beta thalassaemia carrier, and suggested his partner should be tested during pregnancy, but they never expected her to be a carrier.
Father - I went to my local children's hospital as a child for a tonsillectomy. I'd previously had a, an ear operation, the tubes in the ears, as a child, without, without it being picked up. But I went in for a tonsillectomy and a blood test revealed - they said it was, I suppose being white and, and the city I come from, I was quite a novelty really. They'd, I don't think they'd seen a white child with, with thalassaemia. So they went back through, my two brothers don't have thalassaemia, but my father does, which sort of probably accounted for his sort of often fatigued - you know, after, after a hard day's work he was often very drained. And I was the same as a child. And so all, all really we were told at the time, it was, it was like, 'It won't have any effect. It won't really bother you.' I think I was told I shouldn't be a deep-sea diver or a fireman because of oxygen tanks and things. And all I remember the doctor saying is, 'You'll be fine. But you shouldn't marry a Greek girl, because girls from Greece may have this.' Because back then it was a sort of Mediterranean condition rather than a condition that's now spread to the sort of Indian subcontinent.
And so when we met it's, there didn't seem to be any risk that there would be any link. And almost when I mentioned it to our midwife, I said, 'Oh, by the way, I've got thalassaemia minor. Do you think it should be, it should be checked and -?' 'Oh, no, no, I don't think you need to bother about that.' And after talking for a while she said, 'Well, we'll stick it in on the blood test as well.' And I think in this city, given the large ethnic background, I think it is a general policy that they want to extend the blood testing beyond the Asian community. But when we were tested it was just because I sort of suggested it.
Footnote - although being a beta thalassaemia carrier has no effect on your general health, some carriers feel they get tired and anaemic.
(See also 'Partner screening'.)
Occasionally people who already knew they were carriers were asked to have screening again when they became pregnant. For some people this was not a problem, but one woman was angry that she kept being asked to come back for more tests.
Although she already knew she was a beta thalassaemia carrier, she has been tested again in both pregnancies. She does not mind if it helps keep records up-to-date. (Read by an actor.)
Although she already knew she was a beta thalassaemia carrier, she has been tested again in both pregnancies. She does not mind if it helps keep records up-to-date. (Read by an actor.)
Video and audio clips read by an actor.
So when they tested you in pregnancy, did they actually say that they were going to test you for thalassaemia carrier status in pregnancy?
Yes. Even - because on the notes, you know the notebook that you have to complete? It actually says all the listed diseases that you could be a carrier for, whatever, and if you know if you've got it or if anyone in your family have got it. I'd actually already ticked thalassaemia because I knew. So even though they know that I knew, they still, you know, got me tested again, just to confirm it, I suppose, for their own records.
So are you glad you were tested again in pregnancy, then?
Yeah, yeah. They still tested me this time as well. I think so, because even though I had ticked it and they had my notes from before, I think just to keep the records up-to-date, because they don't carry the other records around.
And I have to have a card which I've got in my wallet that I carry around as well, to say I've got beta thalassaemia.
Footnote - there is no need for the carrier screening test to be repeated if there is a valid record of a previous test result.
She knew she was a beta thalassaemia carrier but has been told she needs to be tested in every pregnancy - which has made her both anxious and annoyed. (Read by an actor.)
She knew she was a beta thalassaemia carrier but has been told she needs to be tested in every pregnancy - which has made her both anxious and annoyed. (Read by an actor.)
Video and audio clips read by an actor.
When I fell pregnant with my first child, they insisted that I have this thalassaemia test done again and I'm telling them, “I don't have it.” And then they're sending me all this information through the post, and it's really quite confusing information they're sending out in the post, as well - lots of these leaflets, and really quite scary leaflets as well, you know, that are making you feel really threatened and really vulnerable. And I just read through it and I'm getting really, really angry with them, and cross, about “Why are you sending me this information? I've just found out I'm pregnant and you're making me worry unnecessarily, and I know I don't have it.” But they insisted I was tested again and then they found out it was positive.
But it just seemed like a long-winded process where people keep asking you about it and keep going again. And then recently I was pregnant again, and my doctors had changed now, and I got a very funny phone call from my doctor's receptionist saying, “you have to come in and you have to have another blood test.” And I says to her, “Why?” “Because the doctor's not sure whether there's something wrong with your blood, or it's because of your ethnic origin.” And I'm going, “I know exactly what it is.” And I just started to laugh, really. So I says, “No, I'm not coming.” “No, you have to come.” I says, “No, I'm not coming. I have the thalassaemia trait, end of story.” “No, you have to come.” This is just recently, like 2005. I'm talking about August 2005. And I says, “I'm not coming. I know what's wrong with my blood. And I'm not coming.” “You have to come in. You have to come in. The doctor has asked me to ring you. You have to come. You have to have this test done immediately on you.”
Because when they had my blood tests done, they must have found out that I was anaemic. And that was obviously due to the trait as well. So I just gave up in the end and I have to go and have this test done. And I'm getting really cross with her. I says, “Why don't you just look on the computer and it'll tell you I've got the thalassaemia trait?” “Well, it doesn't say it on the computer that you've got it or not. They must have missed it out when they were transferring all the notes over to the computer.” And I'm just thinking, “You lot are great,” you know? “Really, really great.”
Footnote - there is no need for the carrier screening test to be repeated if there is a valid record of a previous test result.
Last reviewed December 2018.
Last updated December 2018.
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