To (still) be really upset over inaccurate due date

[FluffyDogStory]

My younger DC is now a toddler but when I was pregnant my due date was changed following my 12 week scan to a date almost 3 weeks earlier than my due date according to last period. I said to the midwife at the time I was sure this was wrong, particularly as it was impossible for DC to have been conceived at that time as DH was away from home with work so we hadn’t had sex any time near that date. Midwife told me scan is always more accurate than dates and not to worry about it.

Later in pregnancy I was sent for growth scans repeatedly as baby was measuring small. Again I suggested this might be because the due date was wrong. Staff said that’s not possible.

I ended up going into labour early. 37+2 by the official due date, and around 34+4 by last period date. I told staff on labour ward I was worried baby was much earlier than 37 weeks. They said the scan date was right and not to worry. Thankfully baby was born healthy, but small (especially compared to my first DC). I said I thought baby was earlier than 37 weeks, staff said that’s not possible, I’m just worrying unnecessarily etc. I asked about lots of signs of prematurity - eg covered in lots of vernix, much smaller than my first baby, extremely sleepy even for a newborn. Again was told I’m just being paranoid.

At HV clinic baby was always low on centile chart for weight. One HV even tried to get me to switch to formula as they wouldn’t entertain the idea baby might be small due to being early. Another HV and the GP at 6 week check were the only people who said they thought it was likely my due date was wrong but said it didn’t matter now anyway.

Fast forward to now. DC has some signs of medical issue that is more common in premature babies. GP has said they won’t refer us for help yet, partly because they think DC doesn’t have any risk factors as they are recorded as full term birth.

I feel like I’ve been saying over and over that I’m certain the due date was wrong. I even explained that according to their dates I would have been four weeks pregnant before DH and I had even had sex that month! And yet almost every time healthcare staff have told me I’m wrong and that it wouldn’t matter anyway. Except actually it does matter now if I’m right that DC was premature and possibly has some issues as a consequence.

AIBU to be really fed up that they’ve ignored my concerns about this?

That’s awful OP. Vlassic example of how women’s knowledge of their own health is dismissed and patronised. You are best placed to know when you got pregnant!!

Sorry that no one listened to you 😢

Frankly I don’t understand due dates at all. At my 12 week scan, they decided I was due 10 days earlier than my date based on my last period (not physically possible, I know when we conceived). As a result, I was actually over 14 weeks, so they couldn’t do the usual nuchal measurements. (I was quite annoyed as I’d specifically questioned the late appointment date with the midwife.)

Apparently in France, full term is 40 not 39 weeks, so I’m less than impressed by the usefulness of due dates. Good for you for challenging the dubious logic around this subject and I hope you get clarity around your child’s health needs soon.

I tracked my periods - and temps - and knew when my DD was concieved

She measured 'large' and i was told my dates were wrong (they could not be when they said as we had not DTD. )

Cut to her birth - she came 'exactly' on her due date by my dates - and 2 weeks late by theirs!

I think its is more than frustrating if 'you know' to be ignored!

I had ivf and when I was discharged from the clinic to normal nhs care the clinic told me not to accept any change to my due date based on subsequent scans so I took from that that there had been problems arising from this.

If your husband was away & you couldn't have concieved at the time you were dated at then it's ridiculous that your dates were changed.

My 2nd is in their 20s now but I had to keep going for scans & was told that they were "big for me" & I might need a caesarean.

They were actually a low birth weight!

My midwife accepted straight away when I said I wanted my due date changed to be inline with my IVF transfer - though I don’t think it was far out from the scan. So there are medical professionals who do listen!

IIRC, at 9 weeks the scan measurements are much more accurate for age than they are at 12 weeks.

I would pay for a private consultation related to the health condition that you’re concerned about. Mostly, for your child’s health. But also because I wonder if that consultant could write a letter to go into his notes confirming the possibility of prematurity related to this condition - if that is what they think, of course.

OP can we ask what the condition is?

@Skysblue

That’s awful OP. Vlassic example of how women’s knowledge of their own health is dismissed and patronised. You are best placed to know when you got pregnant!!

Sorry that no one listened to you 😢

Exactly this! We are just the uninformed birthing human who waits to be told by someone with superior knowledge when we conceived our own pregnancies 🙄

I've never really thought about this as DD's scan dates tied in pretty accurately with mine but these posts make me cross on all your behalf's. For some women inaccurate dates will be a mere annoyance but for others it could cause huge added risks to them and their baby, both with preemie babies who aren't prioritised for the care they need and for ladies left without monitoring to go extremely overdue.

When it comes to fetal movements we are encouraged to know our bodies and our babies and trust our instincts. Yet when it comes to conception and dating we are apparently expected to completely disregard our own knowledge of our bodies. I'm sorry you've had such a fight OP and I hope that in years to come women won't have to fight these battles regarding their own bodies and pregnancies.

I had this too. I knew when I conceived because DH was working abroad and came home specifically to shag me as we were ttc. 12 week scan moved my due date a week earlier.

DS was an unstable lie and I had to be admitted to the ante natal ward and wait to have a CS. The hospital didn’t want to do it before 39 weeks due to it being better for the baby to wait. I told them I thought I was 38 weeks but I had measured huge throughout the pregnancy so nobody listened.

DS was born and seemed much sleepier/less aware than 40 week DD, and he was jaundiced. He was 8.7lb which put him on the 75th centile, which was much lower than he had measured during pregnancy. Within 2 weeks he had chunked up massively, gone up to the 99th centile and has stayed there ever since. I’ll always be convinced that he was a 9.5/10lb baby delivered 2 weeks early.

With my second baby who was IVF I had a dating scan that put her two weeks ahead of my actual due date. And I knew this due date was accurate as I had spoken to the embryologist on the day of fertilisation! I had real troubles with this date. In the end I had issues with her not growing due to a badly functioning placenta and my consultant asked me which date I wanted them to go by.

So she ended up born very tiny and early. She didn't need much help in the end apart from regular blood sugar testing and help for jaundice but had she gone on the scan date and she'd needed help she wouldn't have been recognised as premature.

Dates do matter and this was obviously a mistake as I knew her dates from the IVF hospital. But how many babies are given wrong dates?

What did your ds weigh?

Weirdly it turned out that I was pregnant for exactly 9 months. I was shit hot on tracking ovulation after almost 2 years TTC and DD was 8 days "late". I argued over my due date too at the time. Even with all the variables to take into account. Just weird, she was like clockwork.

3 out of 4 of mine had their dates changed as they were measuring larger. I knew when I ovulated with all of them and that the change was incorrect. I tried to tell the ultrasound technician for my fourth that the date she had given me was impossible and was told that he didn't behave like he was 12 weeks, but like 13 so I must be wrong Obviously he was conceived by magic a week before we dtd!

I remember asking when they changed my due date with DS1 and the sonographer very confidently stated that up to 12 weeks all babies grow at exactly the same rate, so the scan would be entirely accurate. As with others they changed my dates (luckily not by much) to something which was physically impossible for when conception happened (I then went into labour on the date I had as his due date, not that that proves anything :) ). When the same happened with DS2 I had a regular appointment with the GP and explained I was concerned about the way the due date had been changed as I wanted to try for a VBAC and in this area if he'd gone over due date at all I would have been considered unsafely overdue and pushed t have another C-section. The GP recognised I knew my dates very well and changed the records :). Just as well as he was slightly overdue

It happens all the time. My first was 3+ weeks early according to them, but my dates had him on time. He was big and behaved exactly as an at term baby. With second they induced me as I was over 2 weeks late- according to my dates he was bang on time. Mind you, the lovely midwife who broke my waters said he would have been in there another month if it was up to him 🤣. He's still like that 14 years later!

The inaccurate measuring seems to be rife. My niece was measuring 'small'. They told her baby would be 4lbs or so and concerned. She had amniotic fluid issues anyway and was sectioned at 36 weeks. He was 6lbs at 36 weeks- so pretty decent, esp.if he'd been in another 4 weeks.

He's now 2 weeks and like a little doll. Adorable.

Midwives know the difference between a 34 weeker and a 37 weeker. Honestly. If he was 6 weeks early you’d have known about it!

Wow I had no idea this was so common. It makes me so frustrated to see how many people have been treated like this too. I’m especially amazed they even do it with people who conceived with IVF since you literally have medical proof of dates!

Looking back, one of the things that annoyed me most was the way staff would first tell me I had to be wrong as the scan date was always correct, and then when I explained it was impossible that I’d conceived without having sex they’d just change their response say it didn’t matter anyway and not to worry.

One midwife genuinely giggled, looked really embarrassed and said she didn’t need those details when I told her I couldn’t have conceived then as DH and I hadn’t had sex. I mean she’s a midwife, how does she think people get pregnant! Another one told me that people’s memory isn’t always accurate (ie that I’d forgotten when we’d had sex), which may well be true, but I’m fairly sure DH’s plane ticket is good proof that he was a few thousand miles away on the date I was supposed to have conceived!

There really is something infuriating about being told that your knowledge about your own body and life must be wrong as it doesn’t tally with the supposedly infallible scan measurements.

Midwives know the difference between a 34 weeker and a 37 weeker. Honestly. If he was 6 weeks early you’d have known about it!

@UhtredRagnarson how do you explain the time of conception being whilst DH is away, or the stories of the IVF babies where fertilisation date is a fact.

Are you saying someone else must be the father in all these cases?

@UhtredRagnarson

Midwives know the difference between a 34 weeker and a 37 weeker. Honestly. If he was 6 weeks early you’d have known about it!

Really? So the alternative is that I was somehow 5 weeks pregnant before even having sex? How does that even work? I’m genuinely curious how this could be the case.

I had a situation where I was pregnant and went for a 2 scans with my fertility clinic. I was 9 weeks pregnant and they said 'you're measuring at 7 weeks so we're changing it to you're 7 weeks pregnant'.
Which was RIDICULOUS as we knew the exact date I conceived as I had IUI with them! So they knew the exact date of conception.

Then at 11weeks they changed the dates again saying I was measuring different so changed the date again which didn't make any sense whatsoever as we knew the date I'd conceived as they were there for the procedure! Really, the baby must have been measuring small so could have been an indicator that something was wrong.

I did miscarry then at 11 weeks sadly but I still don't understand how they come up with this nonsense which feels a little like playing God.

Are you saying someone else must be the father in all these cases?

are you kidding me? Oh of course, this is mumsnet so I must be saying that!

No I’m saying midwives, who deliver thousands of babies at different gestations, know what they’re looking at when a baby is born.

Really?

Yes- really.

So the alternative is that I was somehow 5 weeks pregnant before even having sex? How does that even work? I’m genuinely curious how this could be the case.

No idea. It’s a mystery.

It’s not really so much mysterious as impossible though, isn’t it? Humans don’t conceive babies without having sex (except fertility treatment etc of course). So either my DC was earlier than the date given by the scan, or I conceived without having sex. Which one do you think is the more likely scenario?

This type of thing makes me furious. It's like you're being gadlit by the medical professionals who you should be able to rely on. I'm not surprised you still fell angry. It's stiff having an impact. Yanbu at all.

Could you get any support form a premature birth charity?

I experienced something like this, but the other way round. I ovulate very early in my cycle and was charting, taking temps etc. I knew exactly when he was conceived, but the official dating was based on my LMP which placed him about a week and a half behind.

He measured big all the way through, and when I went over my due date I was quite anxious - I was finally induced at 42 weeks, but by that time I knew he was actually 43.5 and so way over. The delivery ended up being pretty sketchy with his heart rate dropping and eventually ended up with a CS. The placenta was really degraded - the obs team were surprised by this, but of course I wasn't.

Women's voices need to be listened to.

Some info on due dates and why it is measured from scan dates. It obviously not very clear, so I think the medics are just trying to use the best method they can, based on the studies they have.
It does say that implantation date is important, and it varies. So even if you know your ovulation date there may be differences in how long fertilisation then implantation which explains some of the changes.
evidencebasedbirth.com/evidence-on-due-dates/

evidencebasedbirth.com/evidence-on-due-dates/