Table 3 Synthesis of interview themes

1) Physical consequences

1) Of EIS

Unable to feel measurements

“Yes, I don’t- when she did the pen thing, I can’t remember what it’s called (I: The impedance?) Yes. I didn’t even feel anything, or notice anything that was happening. It was as if it hadn’t happened. But it had been done, because I didn’t even notice anything being done. So that was quite good.”

Participant 13

(HR, two MTLs, early miscarriage and three term births)

Unusual sensation experienced

“It’s like a bit of pressure I guess inside-it’s like nothing I have ever felt before. It’s kind of inside and up (laughs) but not painful just…just pressure, a strange kind of pressure which is not a normal feeling; you would not normally experience that.”

Participant 20

(LR, first pregnancy)

Pain/discomfort/negative descriptors

“…it sort of felt like I was getting an IUD (intrauterine device) put in. There’s a little pinch or a poke or something. But I think it’s the way, I think she moved it or something. So it wasn’t actually the instrument, it may have been the handling of the instrument.”

Participant 10

(HR, one PTB, one term birth)

Positive descriptors

“Couldn’t really feel much with that to be honest ummm I felt the swabs more and the speculum being placed than the impedance test, it was more like a very gentle pressure and then hearing the beeps so … yeah it wasn’t uncomfortable”

Participant 14

(HR, one PTB)

Post-test symptoms

“Nothing changed. I mean absolutely nothing changed. There was no bleeding, there was no discharge, I didn’t feel any aching. Nothing.”

Participant 18

(HR, one MTL and early miscarriage, three term births)

2) Of other screening tests

Speculum

“I think for me, the speculum is, not painful, but the most uncomfortable part of it.”

Participant 11

(HR, one 23 week delivery and neonatal death)

Swabs

“The swab is the one that’s, the swab is actually the one that’s uncomfortable… I mean you can feel it, you can sense it… you can actually feel it scraping, even though you know it’s a cotton swab and it’s just gentle”

Participant 18

(HR, one MTL and early miscarriage, three term births)

TVUSS

Yes, like I think the cervical scan is gentler than the rest of it, so I think it’s more having- and especially I think because I’ve had a lot of scans where they’ve used it to look at my ovaries, and they’ve been quite you know, whereas a cervical scan is much softer than that even, because they literally just want to gently go in and they can see everything. Whereas I’m used to cervical scans where you’re really looking for your ovaries and your follicles and stuff. So it’s really gentle. It’s almost like she only really needed to put a tiny bit of the tip in really, just to see what she needed to see

Participant 6

(LR, first pregnancy)

2) Emotional experiences

1) In relation to EIS

Uncertainty re: impending physical experience

“It was definitely far less of a feeling or a pain feeling than I had expected. I expected to feel more invasive.”

Participant 2

(LR, recurrent first trimester miscarriages, first ongoing pregnancy)

Concerns re: safety of novel test

“I was a little bit, I have to say I was a little bit, you know because it’s research and someone’s checking, I sort of felt that if you’re taking part in something, you can’t completely say that there isn’t any risks. So that part of the research, I was anxious about that a little bit, but once I’d finished and sort of a couple of hours later, I wasn’t feeling any different, I mean it was fine

…I wasn’t worried, but I was a little bit- It’s still a risk, it’s still, even though you’re guaranteed 99%, there’s always 1% of these going the opposite way.”

Participant 7

(LR, one term birth)

2) In relation to other screening tests

Impact of visual result of CL scan

“If she had just tried to explain that it is short, but seeing it myself on that screen, it’s made me realise that I can’t be messing about, I can’t be going home. I’ve got to listen to what they’re telling me to do.”

Participant 19

(HR, two PTB and one term birth)

Psychological impact of CL scan results

“It was just really reassuring to know exactly what was happening because you can’t feel anything can you with your cervix, so it’s impossible to know without the scans.”

Participant 11

(HR, one 23 week delivery and neonatal death)

Psychological impact of FFN results

“ The first study visit I did have a slight increase in fibronectin result…. which was a surprise and then a worry as well because obviously I didn’t expect anything to be picked up on it”

Participant 14

(HR, one PTB)

3) During pregnancy in general

Fear and anxiety in pregnancy

“Yes I think for me, it were like a blessing really, because I was already really paranoid about just being even pregnant. I think I was really, really scared”

Participant 9

(LR, first pregnancy)

Falling through the gaps of antenatal care

“P: You know if I’d not had all these tests done, I know for a fact I’d be thinking all the time, is that something? Is that something?

I: What would you have done? Who would you have gone to?

P: I don’t know. I probably would have just drove myself and my husband crazy I think (both laugh). I went to the doctors originally, and the mid-wife. And I explained to them about my anxiousness, and the fact that I didn’t know what had happened last time and how that was making me feel. And I felt that it got dismissed a little bit there.”

Participant 5

(HR, one term birth, one PTB)

4) During high risk pregnancy

Emotional burden of previous obstetric trauma

“I never actually think about it, because it’s been 5 years now. But you’re totally out of control. Like you can’t do anything. You can’t help your kid, you can’t do anything. You just have to like be there and it’s just not how life should begin, that stressful you know… I can’t even look at pictures of her, because she’s so tiny”

Participant 10

(HR, one PTB, one term birth)

Cycle of anxiety in subsequent pregnancy

“And then the day before I come in, apart from this time and last time, I had a really sleepless night because I’m thinking what is it going to show? What’s it going to show? And I can find myself just being laid wide awake, but then once I’d been I can sleep safe and sound again for a couple of weeks”

Participant 5

(HR, one term birth, one PTB)

3) Additional determinants of screening experience

1) The design of the EIS probe

“P: I mean it’s sort of funny looking

I: What do you mean by that?

P: Well I think because it’s long and it’s like lights on it, and it makes a noise…

Participant 10

(HR, one PTB, one term birth)

2) Perspectives on intimate examination

The vagina as a protected space

“A speculum’s a bit uncomfy when you’re pregnant to kind of open you up a bit. And I suppose if you don’t have to have that done when you’re pregnant… Well you’d prefer not to have the speculum if you don’t have to”

Participant 6

(LR, first pregnancy)

Intimate examinations as normal

“I don’t feel it were, like there were no pain at all. It was literally just a bit uncomfortable. That’s all you can, well all I can really say about it, but other than that because it doesn’t hurt, because it’s just a normal thing.”

Participant 3

(LR, one term birth)

Intimate examinations as beneficial

“For me, it’s ok. It’s a little weird, but is not hurting, it’s not pain. I know that it’s just for good things. So I’m not worried…. Maybe that is uncomfy. But because it’s good reason to do it, because you need to know something, you just don’t mind.”

Participant 1

(LR, one term birth)

3) Attitudes to knowledge in pregnancy

Pre-existing knowledge of preterm birth

“so before I had my daughter, I didn’t even know you could deliver early”

Participant 10

(HR, one preterm birth, one term birth)

“No-one knew why”

“I’ve had a premature baby before, and the reasons for that birth were unexplained. So going into this pregnancy, I was quite anxious about it happening again and what may have caused it last time and things like that… you know if I’d not had all these tests done, I know for a fact I’d be thinking all the time, is that something? Is that something?”

Participant 5

(HR, one term birth, one PTB)

“It’s good to know”

“No I know, that’s what my sister says. She’s like ‘oh I don’t even want to think about it’. I’m like ‘yes do, like shit happens, you should know’… But see if I’m trying to think like before all this happened, if somebody offered me this, would I say yes? And I would, yes, I guess I would. Because you know, more knowledge is better than no knowledge.”

Participant 10

(HR, one PTB, one term birth)

4) Screening environment

“I had a blanket over my legs… and the door was locked, and she locked it so I could see she had locked it and there was a curtain and everything…”

Participant 20

(LR, first pregnancy)

5) Interactions with clinical staff

Gender

“She was talking, so she sort of made me feel comfortable, because we continued talking about something completely different to what we were doing. So I didn’t feel- I think the fact that she was a female made it slightly better too.”

Participant 7

(LR, one term birth)

Explanation/ communication

“She was very good at explaining all the way through what she was doing, what it was going to be like and things. It’s a little bit like the dentist we’ve got just now, he talks so that you know exactly what he’s doing, so you never are caught unaware like ‘what was that?’ or you know ‘that felt weird’ or whatever, because if you have that kind of dialogue through it then you know what you’re expecting and what’s going to happen”

Participant 12

(LR, one term birth)

Bedside manner and rapport

“I think as the weeks have progressed, I feel that we’ve got, I feel that we’ve built up quite a good rapport between us, and I do trust her. So she when she said things to me, I’ve been able to walk out and thing ‘well actually she’s told me it’s alright, so I’ve not got to worry about it until next time’. It’s very reassuring

Participant 5

(HR, one term birth, one PTB)

4) Practical considerations for broader implementation of EIS

1) Information leaflet

“Like some of the bits I was like what is that? But most of it…. It was just all technical, well not technical but like, it were just like, I knew all the ins and outs of it so it weren’t too hard.….I would say to mum ‘what is that?’ ‘What’s that one mean?’ I can’t really remember all of it. I didn’t ignore it, I just read a bit of it.”

Participant 3

(LR, one term birth)

2) Timing and frequency of screening

“I think if it was at a time when you were coming to hospital anyway, like the 20 week scan, then I think that would be a really good idea. But like I was saying earlier, it kind of put me off taking part in the study before I had a premature labour, just because of work and commitments and thinking ‘oh I need to take more time off’…”

Participant 11

(HR, one 23 week delivery and neonatal death)

3) Women’s opinions on overall acceptability for wider use in antenatal care

In favour of universal screening

“…yes I think everybody should do it. I don’t know, sorry. I’m just a survivor of premature birth so I’m sort of for everything.”

Participant 10

(HR, one PTB, one term birth)

Dependent on risk status

“P: Whether I’d feel I would need to have it if I’ve gone through two, you know if I’ve had two kids already that haven’t had any premature-ness, then I don’t know if I’d feel the need if it was like you can have this or not have it

I: If it was an option, you think that you would probably decline?

P: Only in that I wouldn’t have the worry if myself to find out whether there was a risk of being premature. But I wouldn’t not have it if it was an offer I think, because the procedure wasn’t anything that you wouldn’t just say oh yes that’s fine, I can just have that as well so I know for sure that things are ok.”

Participant 12

(LR, one term birth)

Trade-off between burden of tests and information gained

“…you’d prefer not to have the speculum if you don’t have to. As a routine measure, it would be, but if it definitely picked up lots of, you know if it was going to pick up the risk of having a premature labour then yes it was definitely worth it, because it’s nothing compared to that”

Participant 6

(LR, first pregnancy)