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Dating at early scan(33 Posts)
Wondering if anyone has a similar experience... my last period was 24th December... i thought I was 8+1 had an early scan today and they said the baby was measuring a 6+1. He said the heartbeat was really strong and everything looked fine but maybe I ovulated later than I thought. Has anyone else had this? I don’t know if the dates add up as I got my very strong positive pregnancy test 26th January..
My dates were a week out. My EDD also changed from an early scan to my 12 week on. I've literally had 3 different dates.
I’d try not to worry. Had you been tracking ovulation?
It’s fairly common to have ovulated later, especially if you weren’t tracking.
My lmp was 21st December, got my positive at 8dpo on 11th January and I’m currently 8+5 (8+6 if I go by what they measured baby at a scan yesterday).
But I know for certain when I ovulated as I was temping and doing opk’s.
I think the fact they’ve seen a strong heartbeat is super positive. With my miscarriages we never saw that, I always dated earlier than expected but never with a heartbeat.
Are they bringing you back for a rescan or did they seem happy enough that you’re just earlier than you thought?
It is possible to measure behind by a fair bit. Best thing would be have a repeat scan to see how things progress.
I've never measured more than 6 days behind on early scans. One I had twins who caught up on growth by their dating scan (almost 6yr now) and the other I lost a week after the scan. All our others 1st scans were their dating ones 11wk onwards.
I had an early scan at 6 weeks which showed I was actually 4 weeks. By my 12 week scan I was only a week behide. I'm now 31 weeks. Good luck. I hope it works out for you.
That’s everyone. They didn’t seem concerned (I asked about 3 times if everything was ok😂) I think I ovulated on 9th January which would be right as the actual age of the baby. I was tracking and I got my most positive OPK on 7th Jan although I never got a peak on them. Perhaps as I was going from my LMP date that added 2 weeks on as that’s just an estimate isn’t it?
If it helps I ovulated on 3rd January (confirmed by temping using OvuSense).
I then got my bfp on 11th.
I really wouldn’t be worried if things looked great and they weren’t concerned.
You could have ovulated and then taken up to 12 days to implant which would account for the difference in weeks.
If you’re going to worry over it then maybe you could book for another scan in a week or so, in which case you should see a difference. Then as long as it’s growing in line with its dates I’d say it’s all good!
I was also 2 weeks behind the date I suspected! Moved back at first scan. I was very certain on when I ovulated but apparently this is a normal occurrence in pregnancy..
It’s taken me a while to get my head around it and not be too worried but I’m now 17 weeks and things seem ok🤞🏻
@Moominmiss that would probably make sense as I had a small bleed on 22 Feb which I thought was my period.. so could have taken a while to implant!
@Leeloo22 oh glad someone else in the same boat as me... I feel a bit peed off that I have 2 extra weeks to go than I thought but as long as baby is healthy.
Congratulations guys x
Sorry meant small bleed on 22nd Jan😂
This happened to me very recently! I tried not to dwell on it but it was on my mind a lot, but all was great at my rescan!
I should have been just over 12 weeks at my scan but I was only 10 weeks, she didn't so much of a scan just showed the good heartbeat and baby shape and booked me for a rescan. As my second scan I was 13 weeks which was quite in line with our refreshed expectation.
It's odd because I could have sworn I knew when I ovulated, but I was only 3 months off the pill and everything was still settling.
I'm sure it's all good especially if they weren't worries at all 🤗
My early scan put me back 10-11 days at least. When I got to my 12 week scan I was only 4 days behind! So they were a good week out! Congrats xx
@Brightspark12 this happened to me yesterday!! I’ve been beside myself all night and can’t stop crying!! I tracked this cycle like a hawk following ovulation induction treatment last month (which was then paused due Christmas) I used OPK and ovulated naturally on 6/7 January. I got my BFP on 19th Jan albeit quite faint but by the end of the week on 24th it was strong line and clear blue saying 2-3 weeks! Yesterday they measured me at 6+1 when I should have been 8+1 or 8+2. There was a yolk sac and a heart beat flickering away. The lady doing the scan was ‘new’ and struggled to understand my questions and couldn’t say if the heartbeat was strong just that there was one. The assistant apologised after and they have re booked me with a different person for Monday. I’m 100% sure on my dates so to be 6 weeks just doesn’t feel right to me and I’m worried sick. We’d been trying for 19 months before BFP and I just can’t bare the thought of something going wrong
Sending positive thoughts to you and it’s good that you were told the heartbeat is strong, I hope it all works out ok for you x
@Blondiebrownie6 don’t panic.. I’ve been doing some reading and NHS use last menstrual period- so which is why we both think we are 8 weeks however you couldn’t have been pregnant on your last period so when you go for the dating scan they don’t look at gestational age (from last period) they look at something called AUA (actual ultrasound age). So you could have ovulated or implanted later as someone else said.. for my purposes I am still going to call myself 8 weeks pregnant as that’s what NHS uses as it’s more likely women will know wen they had their last period as opposed to when they conceived. Even if you are dead certain on when you conceived sperm can have been waiting, ovulation could have occurred later and implantation can have happened later which would affect the age of the baby. I think this is the reason why babies can be 2 weeks later or 2 weeks early as there’s no way of really knowing as there’s so many variables to conception xx
Just to add too, most people wouldn’t have had this info unless had an early scan like us so I’m going to be merrily carrying on with my last period dates and pretend I never had this scan 😂
@Brightspark12 thanks for your response it’s so hard not to panic lol! I knew things could be off slightly but wasn’t expecting that much but it does make sense and I’ll hope for now that I’ve just conceived and implanted later and maybe it’s just a little slower at developing. If it’s measured from conception then 6 wks would be pretty much accurate; DP kept saying this last night and how that would be correct! But was trying to explain to him how it works with LMP. So confusing lol, just need to be grateful for now there is a yolk and a heartbeat and wait it out until Monday for a rescan and hopefully some reassurance (or an honest conversation, but either way just someone to answer my Q’s and talk to me)
I think symptom wise I’ve not had a great deal apart from the sore boobs which are still with me and some aversions (and cravings) so that’s something else for now.
Fingers crossed it’s good news all round xx
@Blondiebrownie6 I know me too when I sat down and thought about it I think i ovulated on 8/9th jan so would work out about right. It is stil worrying though. Let us know how your scan goes on Monday and what they say x
@Brightspark12 yes I will do, I’ll try and keep positive until then do you plan on having another scan at all or just waiting until your 12 wk one now? Xx
@Blondiebrownie6 I don’t think so- I have a tilted cervix and the sonographer obviously didn’t realise so It really hurt when he was jabbing around 😂 I don’t think I want to have another one. Still going to stick to my dates and have my 12 week from my dates- worst that can happen is they say I’m only 10 and get me back for another one xx
This happened to me but in my case I was 100% sure when I ovulated.
We had two more positive scans over the weeks to follow, each time with a strong heartbeat, but growth was always behind where my ovulation date would have placed it.
Sadly we found out at ten weeks the baby had died.
Hopefully you've just miscalculated and all will be fine.
@Botanica sorry to hear of your loss
@Brightspark12 and others that may read up on this post.....it wasn’t good news for me last night and there was no heartbeat detected. I can’t get my head around it but I just knew in my gut something was way off and the dates were too far out. I hate that we saw a heartbeat to start and just a few days later it’s not there, doesn’t make sense. I’m absolutely devastated after trying since May 2019, but back to square 1 for us.
Wishing you all the best with your pregnancy xxx
@Blondiebrownie6 so sorry to hear that you didn’t get positive news at your latest scan.
It’s a truly heartbreaking time. Please just be kind to yourself. X
Really sorry to hear that @Blondiebrownie6... awful news. sending love xxx
I’m in the same boat here...
I went for an early scan today at the EPU due to brown discharge and lack of strong symptoms.
There was a heartbeat and the diagnosis is a “viable intrauterine pregnancy”. However I’m measuring a week later at 6w3d than the 7w5d since my last period. I’ve been told to return for a follow up scan in 13 days. Tempted to go for a private scan to relieve my anxiety.
Oh I am so sorry to hear your sad news. Having been there myself I know exactly how devastating it is. I think in your heart you know something is off but it's a cruel twist of fate to see some hope first, before having it dashed.
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