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Scan date can't be right

(24 Posts)
chelle85 Wed 08-Feb-17 07:26:16

I went for my dating scan on Monday and they have put me 6 days ahead of my dates but exclusing immaculate conception this can't be right. My LMP was 14th Novemeber and due to illness and being away with work the only time we DTD that month was 27th November which fits perfectly for conception based on the LMP. But based on the date I have been given I would have to have conceived on 20th/21st November which is not possible.

I know its only 6 days but it brings my due date forward from 21st Aug to 15th Aug. I had hoped that if I went over that I could get it into September as I was one of youngest in my year and didn't really want that. I know baby will turn up when it wants and I may not get a choice but if it came to induction I would noy now be able to wait until September as that would be more than 2 weeks over based on their dates as opposed to 11 days based on mine

Given that LMP date is more accurate can I ask that they stick with this?

Bluebellevergreen Wed 08-Feb-17 07:27:45

This bothers me too but I have no answer sorry

hrfvenia Wed 08-Feb-17 07:29:25

It's to do with average cycle dates, yours are just different which is normal. Unfortunately I don't think there's much you can do about it! Xx

TheWiseOldElf Wed 08-Feb-17 07:35:34

I have the same issue. I'm consultant led due to a previous emcs so I raised it with the consultant who said we should use the adjusted dates for now but reconsider at the end of the pregnancy when induction is discussed (which it will be as I went 9 days over in both my previous pregnancies). Consultant said she would fully support me in declining induction based on adjusted dates. It might come down to size for me tho as I have had relatively large babies (9lbs+)

chelle85 Wed 08-Feb-17 07:35:41

My cycle lengths aren't different though. LMP 14th Nov would give OV date of 28th Nov on average cycle. We DTD day before ov date which fits perfectly with average cycle. I would have had to ov and dtd deed on day 7 of cycle for scan to be correct and as we didn't dtd until 27th it can't be right

CatsCantFlyFast Wed 08-Feb-17 07:37:21

It's because they're measuring something tiny and it's not totally accurate. Honestly don't worry about it. They will adjust it again later when they take different measurements. A due date should be called a due month - it's not an exact science and your baby can easily come two weeks either side of the date they give you and that's all in the range of normal

chelle85 Wed 08-Feb-17 07:37:23

wiseoldelf -that is good to know. Hopefully midwife will be agreeable to that

stresshead84 Wed 08-Feb-17 07:38:00

I really wouldn't worry about it. I don't know if it's nationwide, but certainly in my local authority, you can defer summer born children very easily now. So then they avtually become the eldest in the year. Also, every child is different, some summer born children are very ready to start school at just turned 4, while other autumn or winter born children are not ready at 4.5, nearly 5. At reception age, sometimes you can tell who the summer born children are within a class, by Year 6 (age 10/11) I think I would struggle to pick them out. With respect, you are overthinking this I think due to your experiences. Please don't worry about this. It's a cliche, but true, as long as the baby is healthy it really doesn't matter.

CatsCantFlyFast Wed 08-Feb-17 07:38:09

And as somebody has said, induction if you go over is something you can decline - you can opt for additional monitoring instead, so don't worry

adagio Wed 08-Feb-17 07:38:32

Similar but different reasons for me with my first - I knew they were wrong and I was right and needed my dates to fit due to work issue (impending redundancy). Argued my point throughout pregnancy and made sure it was noted and eventually got my dates updated when growth scans matched up 'my' dates - but they didn't change till 34 weeks!! But ultimately avoided 'early' induction. Arrived at 40+4 on my date.

MumBeth Wed 08-Feb-17 07:46:19

My due date has changed 3 times. Originally 1st August (from LMP) then 30th July (7wk scan) and now 27th July (Dating Scan). I asked my sonographer about the changes and he said dating scan is most accurate due to baby's growth point after 12wk being best indicator. LMP gives a rough idea but cycles can change slightly and baby growth depends on various things not just the cycle. He also pointed out most 1st babies are born after their due date. Hope that helps?

MumBeth Wed 08-Feb-17 07:49:01

Thinking about it after reading adagio's post, maybe most 1st babies are late because LMP dates aren't listened to? Haha.

chelle85 Wed 08-Feb-17 07:49:34

Thanks all. Good to know it is moveable based on later measurements. If baby turns up then they turn up and I know it isn't a massive deal but I don't want to be induced at only a week over because they have me 2 weeks over. I also don't want to end up starting my mat leave earlier and end up being off for ages before baby arrives

minijoeyjojo Wed 08-Feb-17 07:57:56

I had a similar thing with my DD, the due date they gave me was just not possible! I ended up being induced and because I was '15 days' over due and had to go to the labour ward instead of birth centre. I'd fought as long as I could but they'd piled on the pressure and kept on telling me how risky it was, in my vulnerable and emotional state I couldn't fight any longer. It took me a while to come to terms with the fact that the birth was so far removed from what I'd like and I do blame part of that on the early due date they gave me. A few more days may have made all the difference.

I don't want to be all doom and gloom, but I'd speak to your midwife about it. My experience of the hospitals here is that they are very inflexible around dates and no one listens to you when you say that the due date was too early they just pile on the pressure to be induced. Equally it restricts your options for where the baby is delivered if you go too far over. So it is important that they've got it right.

chelle85 Wed 08-Feb-17 08:16:51

Thats the thing minyjoeyjojo. I would like to avoid bring induced at all if I go over and the early date means that they will be pushing for it when I am actually only 1 week over. It may not come to that, I may pop early! But as a lot of first timers go over it does concern me

mumxof3x Wed 08-Feb-17 08:17:33

Mine was definitely wrong, they put mine back which meant I had a positive test 5 days after conceiving according to the scan. I also know when I ovulated due to bad ovulation pains. I did challenge this because I had history of premature birth and knew my baby would be taken as more prem than she was if born early but they wouldn't budge with it. They said they can only go by the date given by scan, even though it was impossible.

As it turns out, I started with all the labour signs at 23+4 by their dates and 24+1 by mine. My hospital were not prepared to do anything because I was below 24 weeks....even though I technically wasn't. Luckily my daughter held on longer and I went into labour at 30+4.

MoonlightMojitos Wed 08-Feb-17 17:23:00

I'm in the same position, was moved forward 8 days at my dating scan although I know for a fact when we conceived to the day. At my 20 week scan baby was measuring slightly on the small side for all measurements but they havnt adjusted my due date. I'm not worried for now and like you said baby will come when it's ready not when the date says it should! I'm hoping I won't go 2 weeks over due but will face that when it comes if they want to induce when I know I'm a week behind what they say.

Snowflakes1122 Wed 08-Feb-17 20:23:19

Really wouldn't let it bother you. Scans are accurate within +/- 7 days so not perfect.
My son always measured a week ahead on several scans too. Think he was just a big tall boy (still 90th centile on height at 2)

SharkBastard Wed 08-Feb-17 20:25:37

I'm measuring 6 days ahead, I'm 29+3 in my workings (which are correct as we only DTD once that month...was a shit month) but they've dated me as 30+2 and that's the end of that.

I will insist they wait 6 days for any induction before 40 weeks cause I know my dates

Rollonbedtime7pm Wed 08-Feb-17 20:31:44

My last baby was dated 2 weeks ahead of what I thought - I knew when we had DTD and she was my 3rd so I also knew my pattern of when symptoms appeared after conceiving.

They never changed it though, even after 20 week scan and she was born smack in the middle of their date and mine (my previous 2 were early so I still think mine was most accurate!)

She's here now though so meh... it won't really matter. As everyone has said just talk to your midwife about hanging on as long as possible at the end if you need to.

annlee3817 Wed 08-Feb-17 20:51:27

They won't adjust your due date after the dating scan. Mine put me five days ahead, and meant conception would have happened when we didn't do the deed. I actually went into labour on my early scan due date and the date I calculated from when we had done the deed.

As someone else said you can defer school for another year, my DD was born in June and we have the option to delay if we want to. I was an August baby and don't feel it affected me.

harleysmammy Wed 08-Feb-17 22:57:24

I dont think scan measurements are really that accurate or exact - at least thats what my midwife told me at my 12 week scan. I dont know exactly what day i conceived i knew the last period i had so i should have been due on the 4th of may this year, but at my 12 week scan they said im due 2nd of may instead. I know thats only 2 days but im now 28 weeks and since 18 weeks, he has been measuring a week and a half ahead of himself. In fact i had a scan last week at 27 + 2 and he was measuring 28 + 5..he could be a big baby or they could have just got my dates slightly wrong the first time around. Your baby might just be a big baby x

vfoster Thu 09-Feb-17 07:31:43

Exactly the same happened to me! My due date was moved from the 21st July to the 16th at 12 week scan and there is no chance it could be right!
I explained this to the midwife and she said the baby probably just measures a bit bigger. My first child was 10lb 10 as she is really long! My husband is 6"5 and I'm 5"8 so doubt we'd get a little baby anyway.
As previous posters have said, they can change a few times throughout pregnancy.
My daughter's birthday is the 27th August and to be honest, she would be frustrated to be in nursery for another year so it's worked out well her being one of the youngest!

Rollonbedtime7pm Thu 09-Feb-17 09:42:13

Yes, not always a good thing to be the oldest in the year - my DD1 is a September baby so she missed school this year, my God is she bored!! Finding it really hard work to keep her busy!

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