Antenatal Screening
18-20 week antenatal scan (low chance)
All women will be offered a 12 week dating scan and an 18- 20 week mid-pregnancy scan also known as the fetal anomaly scan.
The purpose is to check the baby is developing as expected and to look for any serious health conditions, such as heart problems, spina bifida or chromosomal conditions such as Edwards’ syndrome and Patau’s syndrome. This can help parents decide whether to continue the pregnancy. It can also identify problems that may benefit from early intervention following delivery and in some cases interventions that can be carried out during pregnancy.
Most people we talked to were broadly aware of this purpose. Some of them felt very well prepared, while others would have liked more detailed information about what the scan looks for.
The information about what the 20-week scan was looking for was very thorough.
The information about what the 20-week scan was looking for was very thorough.
Mother' Yes. The information that we got about the twenty week scan from the hospital really explained in a lot of detail what the scan was for and what sorts of things they would be looking at. And so we were nervous, obviously, going into it because it had really set out what things could and couldn't be found as part of the scan.
But in a way that was also really good that you had a much better idea of how long it was going to take and how carefully they would need to look. And as they were doing the scan they explained a lot about the measurements that they were taking and why they were taking those measurements.
Father' And even things like unfolding its hands, wasn't it? She said they really like to see that.
Mother' Yeah, she was waiting a long time. She said, "Oh I'm trying, I'm just staying here because I just want to see if the baby unclenches their hand, because that's good. We like to see them opening and closing their hands." And then as she was doing it the baby went like that and waved.
One woman who had a scan in California felt her doctor in the UK explained it better. Another suggested the person doing the scan should check that the woman was properly informed. She noted that some scan technicians do a quick check for themselves before turning the screen round to face the woman, which may be a sensible precaution in case something is wrong.
The doctor in California who did her 20-week scan did not explain as well as her doctor in the UK.
The doctor in California who did her 20-week scan did not explain as well as her doctor in the UK.
To be quite honest, I'm much more impressed with the things that have happened here than I was with my doctor in California. I went to my Mum's doctor in California and he was a perfectly nice man, I'm sure everything was fine, but it was just little things like I couldn't, like I didn't think that the ultrasound machine was as good.
I couldn't see, like it was frustrating to have this anomaly scan but not be able to make out any of the baby's body parts, and not to have things pointed out to me as much. So I was actually very happy to be coming back here and having the baby.
So you felt they didn't really explain enough about what they were doing or...?
Yeah, it was, I, I felt like I would have liked to know what an anomaly scan was and what they were checking for. I mean, I knew they were checking for problems with the organs and things like that. But I found it hard to follow the whole thing.
I mean, I felt a little bit out of touch with what was going on. I would have liked more information about what they were doing. I got copies of my, of the medical records or whatever from my doctor in California to give to the doctor here and the doctor here pointed out a bunch of things that the doctor in California had never told me about.
I mean, they were in my file and they were there but he had never explained it to me. And I thought that that was strange that it took my doctor here, reading the notes from that time in California, in order to explain to me what this other doctor had done.
You clearly knew knew, the fact that you used the term anomaly scan, it was looking for defects, but was it just that you weren't quite clear which defects they might be looking for or...?
I think that, and just the actual process of when they have the machine on your tummy and they're clearly looking at specific organs, I would like to have been told, 'So here's the brain, here's what we're looking for as we scan the brain'. Or, 'Here's the kidney'. I mean, I don't even know if I'm choosing correct body parts.
This is how clueless I am. But I would have just liked to have been told what they were looking at. I mean, I couldn't, I felt a little hopeless because I couldn't see anything on the screen that looked like, 'Oh, that's a kidney' or anything like that. So just a little bit more information would have been nice.
I think that all doctors, they do this every day, I mean, they see pregnant ladies all the time, so I think they know exactly what's going on. I think that there can just be a little lack of communication between the doctor and, particularly, the first-time mother who is clueless and scared.
Some people saw the 18-20 week scan as somehow different to screening. They were not aware that terminations can be carried out at any stage of pregnancy where there is a severe abnormality.
The 18-20 week scan reassures the vast majority of parents that their baby looks fine. Women described many positive aspects, including
- The joy of seeing the baby and having a photograph
- Feeling closer to the baby
- Making the pregnancy seem real (especially for partners)
- Finding out the baby's sex, although this is not always possible or permitted.
She really enjoyed seeing the baby at the 20-week scan. She would have liked to choose which...
She really enjoyed seeing the baby at the 20-week scan. She would have liked to choose which...
Great, I loved them, I loved them. Just the fact that I could see my baby on the screen was just like wow, it was just amazing.
Did you go on your own?
No, with my partner, his dad. But no I didn't find them uncomfortable or anything like that. They were brilliant. And as I said, the fact that I could see my baby it was just like I didn't really want to leave. They used to give me extra long scans.
And what sort of, did they talk to you during it or were they...?
Yeah, yeah.
Right, so you felt you were getting enough?
Yeah. But the only thing that I had a problem with was when they took the pictures at five months. I wanted, because I wanted a specific picture, like his face and then like - but the doctor literally just scanned me and then said, "Oh here's your photo," sort of thing. And it was like, "Oh I don't like this photo," I had that kind of... But yeah, at my first scan at three months they asked me, "Oh do you like that one?" and we were like clicking away sort of thing.
The 20-week scan was a moving experience and the person doing the scan explained everything very...
The 20-week scan was a moving experience and the person doing the scan explained everything very...
She was the first person that we had contact with who did speak directly to us, who, you know, asked, 'How is your day going?' And 'This is what I'm doing, and I'm going to put the jelly on your tummy, and you look over here and you can see the', you know. And she explained what we were looking at, and she explained what she was looking at, and she said, 'OK, here's the kidney, they're good. And here's the heart, and then you can see the heart on the monitor'.
And she was really interactive, and it was very helpful. And it was a very moving experience. I remember it brought tears to my eyes to see the baby for the first time and to, you know, see his little heart beating and see him moving, moving around and his head and so on.
So I do remember that experience as being very warm and pleasant and just a very happy - it was hearing the heart beat for the first time was the first sense of reality. This was an even bigger sense of the reality that there is a real living baby inside.
One woman who had to have an internal scan (using a vaginal probe) because of the baby's position found this did not spoil her enjoyment of the scan. For some people, having to have a full bladder, especially if the person doing the scan then pressed hard on their abdomen, was a minor drawback. Two people mentioned they had heard that the sound waves in a scan may distress the baby, but there is no conclusive evidence for this.
Although most people said scans had made the pregnancy seem more real for their partners, for one father it was buying baby clothes that suddenly made it feel real. One mother felt the 18-20 week scan was an anti-climax after having seen the baby before. A few commented that the quality of the pictures was poor, but other people were impressed by the quality. This may depend on the type and age of equipment being used.
Although he enjoyed the 20-week scan, it was buying baby clothes that made the pregnancy seem real.
Although he enjoyed the 20-week scan, it was buying baby clothes that made the pregnancy seem real.
So, for you it didn't sort of say, 'Ooh, suddenly, this is my baby. This is real'?
No, to be honest the first time it really came home to me that we were having a baby - obviously intellectually - but emotionally, I suppose, the first time it really came home to me was when we actually bought some baby clothes and you started to visualise a real baby inside these body suits.
So that was before the birth?
Yeah, just 2 weeks before.I mean, it wasn't that I was unprepared but, emotionally, I think that was the first time it really came home.
That's interesting, because often people say, you know, the scan is the point at which it suddenly becomes real for them.
Right.
That this is actually happening and there is a real baby there.
Yeah, but I mean I've heard it said, and read that, you know, for some people it isn't until they've had the screening that they start to bond with the baby inside them, because they still have this kind of opt-out clause, which I think is very sad.
The 20-week scan was reassuring but not as exciting as she expected, and the pictures were unclear.
The 20-week scan was reassuring but not as exciting as she expected, and the pictures were unclear.
To me it seemed really indistinct, lots of bubbles all over the place and the odd body part floating in and out of view, but how they were all connected together was very, it was totally obscure. And that, and we were relying on the ultrasonographer to interpret to a large extent the images and saying, 'That's a foot' or, 'Can you see the spine?'
And if I was being totally honest, I couldn't really. I mean there were some parts that I did see but it wasn't like seeing your whole baby on the screen or, I mean we saw its mouth open at one point which was, you know, quite entertaining but . . .
Did you get a picture? Did you come away with that?
No, we didn't because there was you know, it wouldn't have meant anything. There was no one image that we could have said, 'Take a picture of that, it'll show us our baby'. I'd heard from friends that it was just an amazing experience to see, you know, a really fully formed baby on screen and so I suppose I was expecting a certain sort of completeness to the image and that didn't happen for me.
And also the ultrasonographer had trouble getting the baby into the right position to actually get, to actually do the sort of diagnostic tests that he needed to do on the spine. He just, the baby was in the wrong position and it got to the point where they were saying, 'Oh, you know, we can't actually see what we need to see for this final category of check and you'll, perhaps the best thing is for you to come back again another day when the baby's in a different position.'
And I must say I had, I wasn't particularly keen to take that option up. And fortunately the baby ended up co-operating and moving at the last minute so they could do it, but they seemed to have trouble generally getting the right presentation on the screen. Which was the same actually with the first scan with this pregnancy. So I don't know if it's something about the way the baby's positioned at the moment.
A very important concern for people was the way the person doing the scan (sonographer) communicated with them. Some people could compare different experiences; one woman had a senior consultant the first time, who was expert but brief, whereas the second time the scan was performed by a specialist midwife who recognised what an important emotional experience this is for parents.
Some sonographers talk throughout the scan, explaining what they are looking at and whether it is as expected. This approach was preferred by virtually everyone we spoke to, including a French woman and her British partner who had their scan in France.
At her 20-week scan in France she was given detailed information and explanation. She and her...
At her 20-week scan in France she was given detailed information and explanation. She and her...
Then he went to the neck, the throat, and there was, how do you call it? slices, that's how he called it, slices of the body. He went through the heart and again the flux of blood going through the heart. It was funny, well, quite a nice shape, actually, the heart, the slice of heart.
Then he went through the lungs and the oxygen going through the lungs, and then the belly and all the organs, the liver and all that. The he skipped the middle part, because we didn't want to know. And he went through measuring the hips and the legs and the knees and the toes and everything possible, because my husband was born with, club feet?
Club feet.
Yes. My husband straight away asked, 'Oh, is his feet all right?' and the doctor said, 'As far as we can see they are all right. We can't confirm that they will be all right later, but as far as now is concerned yes, everything is fine.' So that was quite nice to again hear the heartbeat, and hear all the fluids going from me to my baby's body. That was rather nice, and we kept, a very long spreadsheet with all of the, you know, these heart beats and fluid beats and slices of bodies.
So he was talking all the way through, pretty much?
Yes. And the nice surprise was that he was fluent in English, so he was talking it through it with me in French and then translating it into English to my husband, who was delighted to actually understand all these strange words.
And it sounded from what you said as though he did try to say, 'This is only, we are hoping that everything is alright, we can't confirm.'
Yes, yes.
So you felt you came away with an understanding?
Reassured, yes, reassured especially for my husband who was making a big point of it. Reassured, but we knew that, I mean, if something wrong was happening there was nothing we could really do about it and there's nothing the doctor could do about it either. That was one of these things of conception - you never know what's the surprise going to be at the end.
Staff who are talkative during a scan may suddenly go quiet if they notice something unusual, and this can create worry. Some staff explained that they would stay silent while they concentrated on the scan. Most people we talked to still felt they would rather know immediately if staff had seen something unusual.
A moment of worry was described by a woman with previous experience of a scan which found the baby had died. She would have preferred a more immediate explanation.
When staff spotted something unusual during the 20-week scan, she was very anxious and would have...
When staff spotted something unusual during the 20-week scan, she was very anxious and would have...
Father' Great.
Mother' That was great, wasn't it? That was, it was fantastic. It was, and that was incredibly reassuring for us, because the there was one bit where - oh, it was awful wasn't it? There was one part where she was doing, it had all been going swimmingly and it was fantastic, and it was so reassuring to see every part of the baby, apart from being able to tell what gender it was which I'd really wanted to know and they couldn't tell me.
But it was all going fantastically and then she sort of said, "Ooh, ooh. Ooh, I'm not sure, I think I, I just need to go and check with, I would like someone else to come and look at this." And of course then we were just in complete horrors, and I had, and another, another - I can't remember what the name of the people is who does the scans
Ultrasonographers
Mother' Yes, the ultra?
Sonographer. Or it may have been a doctor.
Mother' No, it was another ultrasonographer came in, and I had a placental strand. So it meant that part of the placenta, there was a separate part of the placenta and it looked almost like a thick hair. It was not that, she showed me it on the screen and it was at the top of the womb, so it wasn't - she said if it had been across the cervix it would've been, they would've been more concerned about it, but because it was out of the way and it wasn't impeding the baby's movement at all they weren't concerned about it.
But that was a horrible two minutes while she said, "Ooh". And I wish she'd said something like, "Oh, I think I can see this. I need somebody else to come and have a look. It's not a ser-, it doesn't matter." And maybe she did try to do that a little bit, but it didn't allay, we were sitting in complete terror for a minute while she went and got somebody else to come and check with her.
Father' Well, I'm not sure I would say quite that, I felt from her tone that it was fairly, she didn't seem overly concerned, to be honest, I felt.
Mother' It obviously didn't make any difference to me then, I was absolutely terrified.
Father' Yes.
Mother' For me it was still terrifying, even though [partner] felt, you felt that she was being upbeat about it and that there was something that she needed to check but it was OK. For me it needed to be super upbeat for me not to be absolutely terrified, it would've really needed to be, "This really is OK. This really is OK. There's just one thing I need to check, I'm sure I know what it is and it's absolutely fine," and it would've really had to have been.
Because otherwise, I guess it's that whole thing about how much you take in when somebody's explaining things to you that you know nothing about, and it's like anything with any condition or to do with doctors or whatever. You realise, it's only afterwards you realise how little of the conversation you actually took in and what feeling you got from that.
One person thought it must be difficult for staff to check if there is something they are not sure about if the woman is watching throughout.
It must be difficult for the person doing the scan to check something they are unsure about if...
It must be difficult for the person doing the scan to check something they are unsure about if...
Whereas if I - yeah, I'm sure with my first two they did do a scan, but I just, they said, it was a case of, 'We're checking this, this and this,' and, you know, they got on with it. And then, 'We'll see if we can find a picture so that you can see it,' and then they'd turn it round.
So that was sort of a, it's a bit like when they actually let you hear the heartbeat, but you know that that's not really why they're doing it. They're not doing it so that you can hear the heartbeat, they are doing it because they're checking that everything's OK. So I think yes, it probably does make it different, but I think it must be harder for them to actually check something out if there's something they're not sure about.
Were there ever any -
Because it's more obvious.
- any moments in either of your two latest pregnancies when they were doing the scan when you thought, 'Ooh, have they found something?' Anxious moments?
Well, I think this business when she couldn't, she couldn't trace down all the vertebrae. Because it was quite clear that she was trying to do so, or that she was trying to do something. I mean, at least, she was at least good enough to tell me what it was she couldn't do.
Well, I was going to say how much did they talk to you in each case about...?
They talked quite a lot. Certainly with my third one, I can remember them talking through 'Now we're looking at this, now we're looking at that. We're just checking this, and you can see that the heart valves are working' and things like that. I can remember that. It was great.
A few staff did not explain they would be silent, and this made some people worry. This is discussed further in the '18-20 week scan (being told something may be wrong)'.
Not talking was sometimes more to do with pressure of work. One woman felt staff did not have much time to communicate properly and came away anxious that something might have been missed.
Although some people had gone to the 18-20 week scan alone, most felt it was important to have someone with you for support. Two women said their partner had missed the scan because they were still trying to find a hospital car parking space.
Many experiences discussed here are common to other types of scan - see also 'Early dating scans' and 'Combined screening for Down's syndrome and other chromosomal abnormalities'.
For further information on screening tests please see our pregnancy resources.
Last reviewed July 2017.
Last updated July 2017.
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