The madness of modern measurement

25607878166_a49205ea4aCassie, who has given me permission to tell her story and who chose her own pseudonym, became pregnant via IVF. She was thus one of those women who know the exact date when they conceived, and she and her midwife joked about this at her booking visit. They then calculated her estimated date of birth (EDB) together, using her conception date as the point from which to calculate her EDB. The date they came up with was September 1st.


The ultrasound appointment

Not long after her booking chat, Cassie attended an appointment for an ultrasound scan. Her reason for going was not the dating element of this procedure, but she wanted certain screening tests which were only available at this appointment. Cassie had read loads about pregnancy, birth and decision making and was well-informed even before she became pregnant, so she wasn’t entirely surprised when the ultrasonographer looked at her halfway through the scan and informed her that her due date was different from September 1st. According to the ultrasonographer, Cassie’s baby’s guesstimated due date was August 27th.

Smiling, Cassie told the ultrasonographer that, as this was an IVF baby, she was certain of the due date. Afterwards, Cassie told me that she relaxed again after imparting that information, thinking that she and the sonographer would share a laugh and move on, with her initial due date intact.

But no.


Preparing ahead

Initially, Cassie said, the sonographer seemed a bit flummoxed. ‘I wondered,’ Cassie wrote afterwards, ‘if she wasn’t used to women who had had IVF, but surely she sees lots of us – unless she’s new?’

We never found out how experienced the sonographer was, but that element of the story became less important as Cassie continued her tale. ‘Anyway,’ she told me. ‘I said to her that I didn’t want my due date to be changed. I didn’t want to be forced to have conversations about induction four or five days earlier than necessary.’ As a result of her reading, Cassie realised that one key element of avoiding unwanted pressure to have induction for so-called prolonged pregnancy was to ensure that any EDB calculated in early pregnancy is as accurate as possible.


Finding a solution

As Cassie explained this during the scan, she felt that the sonographer understood the problem and Cassie’s rationale for wanting to stick with her original EDB. At this point, Cassie told me, she assumed that the sonographer would simply make a note in Cassie’s notes that the original due date stood, and continue with the screening element of the examination.

No, again.

Cassie remembers the sonographer saying, ‘let’s see if I can make this right’, as she placed the transducer back on Cassie’s tummy. She then proceeded to continue to measure Cassie’s baby from a variety of directions, and it slowly dawned on Cassie what might be happening. A further chat with the sonographer confirmed Cassie’s suspicions. The sonographer knew that the final due date calculated by the scan procedure would be entered into the hospital computer and would usurp Cassie’s original due date. Without the ability to over-ride the authority of the computer-generated scan date, the sonographer was instead trying to re-measure Cassie’s baby in a way which would make the machine generate a due date to match the one worked out from the knowledge of when Cassie had actually conceived.


An isolated problem?

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Sometimes, when I hear stories like Cassie’s, I wonder if I have accidentally entered an alternative reality. It wouldn’t surprise me at all to wake up and find that I had fallen asleep on the sofa while watching one of the Terminator movies, but that turned out not to be the case on this occasion.

However, it’s only fair that I add here that I am only able to report one side of this story and haven’t had a chance to speak to the sonographer who saw Cassie that day. So I was concerned that, before I wrote something on this and potentially missed an important point, I should check with a few colleagues. Amazingly, within a week of being contacted by Cassie, I had been told similar stories about three other women. I have also since talked to sonographers who confirmed that, like many other health professionals, they sometimes have to work with systems and machines whose programming prevents humans from trumping the decision of the appliance of the day.


Technological tenacity

I’ve encountered other examples of situations where technologies, machines or systems are limiting women’s decision making. In one area, midwives are not able to properly book women unless they record their height and weight so that the woman’s body mass index (BMI) can be calculated. Yet women have the absolute right to decline to be screened in this way, and some of them decline to be weighed and measured precisely because they know that they are better off (in terms of the options that will remain available to them) if they have an unknown BMI than if they allow their higher-than-average BMI to be documented. In fact, I know midwives who ensure that women know the pros and cons of consenting to BMI measurement before asking whether this is something the woman wants. But such a woman-centred approach leaves midwives in that region with a dilemma because, without a BMI, they can’t even get to page two, let alone complete the booking appointment.

In this situation, and many other similar ones where computer systems want information that women may not want to give or that midwives may not be able to provide, the midwife’s options are limited. Stopping the data entry isn’t really an option, and the impersonal, impenetrable stubbornness displayed by a computer is absolute and cannot be reasoned with. In some cases, practitioners have no option but to make something up in order to be able to get on with their work. (Fast forward, by the way, to the next audit or research study which draws on data gathered from these systems, and we have yet another reason to need to be extra vigilant about results based on medical records).


What can we do?

Often, when I write articles about things that aren’t working well within the maternity services, I know that there is nothing much that individual midwives can do about the problems. But, actually, in this case, there IS something that we can do. These machines, computers and systems are authorised and bought by people who work for health care systems and, if the machines are not serving the recipients of those health care systems well, then we should tell those responsible for their purchase. If you don’t want to do this as an individual, then there are a number of groups – such as MVPs and PALS – who may well feel able to take your concerns forward. Let’s not sit by and let machines dictate women’s experiences in this way.


This article was originally published as Wickham S (2016). The madness of modern measurement. TPM 19(6):39-40.


If you’d like to learn more about post-term pregnancy or similar topics, chat with other midwives and birth folk about dating pregnancy and build your confidence with the evidence, I’d love to welcome you to my online course on this topic 😀  And you can keep up with my research postings via my free updates and monthly Birth Information Update.


photo credit: michael_durden 11 19 15_19 via photopin (license)

8 comments for “The madness of modern measurement

  1. Helena
    December 1, 2016 at 7:22 am

    A well timed post. Thank you. I have been having just this discussion with a student this week. Case 1. Woman planning a home birth, her scan estimated due date was last week yet that would mean she conceived whilst menstruating, she is now concerned that she will go past 42 weeks which will take her outside of”normal” and will face a struggle having the home birth she wants. Case 2. Exactly as you have described. It’s utter madness that womens knowledge of her own body is over ruled by something which we know can be inaccurate. And don’t get me started on “large for dates” babys!

  2. Sally Randle
    December 1, 2016 at 11:08 am

    When dating scans first came in (at KCH where I trained and worked this was very early on because of the Harris Birthright Trust upstairs) we were told that if the scan changed the date by plus or minus 5 days to use the LMP date when known, to allow for (I assume) human error since it is a human holding a large clumsy scanner trying to measure a tiny tiny thing doing the scanning. This has long since gone out of the window. The woman in the above case would not have had her date moved if they still did this. AFAIK the dating scan was brought in since it was felt to be most accurate in assessing EDB, in order to reduce the induction rate for “prolonged pregnancy”. Has this been audited by anyone? That this has been the result? I doubt it very much.

    • Geegee
      December 1, 2016 at 10:06 pm

      I did that last year and I’ll be doing it again this time as scan measured me four days over. I’ve got final exams around edd, I’m not going to add to stress by arguing with them so will change at my 16w midwife apt 🙂 silly machines overriding brains!

  3. Sue Kinross
    December 1, 2016 at 12:02 pm

    Hi Sara (long time no see!)
    I wish with all my heart that this madness would go away! In a similar way, I looked after a couple who were both tall people – both over 6ft – and naturally the ‘due date’ calculated by measurement of the foetal femur was considerably different from the date that was based on conception and menstrual cycle. The system makes no allowances for individual differences. A tall couple are likely to have a baby with long thigh bones, yet the date that was entered on the computer was a whole week shorter than her date. The pressure on her was incredible and this woman was made to feel that she was a risk-taker as the date for her homebirth came and went. The baby decided to arrive at the perfectly acceptable 41 weeks – but recorded as 42 weeks by the hospital. She went on to have three more homebirths – all of which were ‘long’ babies and all came after 40 weeks. Each time, she had to endure raised eyebrows and tutting and even on one occasion, a lecture on shoulder dystocia risks associated with post-term babies. (Since when was 41 weeks post term?)
    I S

  4. December 1, 2016 at 10:22 pm

    Not to mention the induction “discussions” at 41 weeks where Medical Care Providers dismiss the woman’s own knowledge as irrelevant in comparison with the computer – I have also had a client where she knew her date absolutely, but was told her date “was” a week earlier despite the fact that that would have put her partner out of the country at the time…!

  5. Mary Seager
    December 2, 2016 at 1:23 pm

    You have touched on a very sore point with me – the inability of modern society to operate outside of ‘The Computer’ (bow down low now…)! It is ludicrous and whereas in ‘normal’ life it is just frustrating and anger-producing, this aspect has severe implications for healthcare. It should be more widely known in the public arena so that women are given confidence in their choices and ability to say ‘no’ at such a vulnerable time of their lives (who would want to ‘endanger’ their precious unborn – the implications made..) But also, as you mention, the skewing of future research has to be borne in mind. Which bears out my inherent suspicion of the accuracy of ‘surveys’….

  6. Emma Ashworth
    December 3, 2016 at 7:47 am

    Great post. Deeply worrying that women are having to persuade the health carer of her own dates in order to avoid the pressures of induction “at the other end” because it shows the level of coercion and control that’s happening, not informed consent or declining of treatment.

  7. Mairéad White
    December 11, 2016 at 12:37 pm

    This is really poor system design that is clearly not governed by principles of Quality Assurance. This should be reported as a QA issue by anyone reliant on the data gathered. I cannot see how thishe system design would pass an audit.

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