Confused by "weeks" at early scan - help please!

[Caffeinedetox]

Hi all,

Following a MC last summer, I found out at Christmas that I was pregnant again.
We're both obviously very excited but anxious and worrying too after last time!

Last week I had a (quite heavy) bleed on Monday night but literally lasted a couple of hours and then cleared up. No cramping or clots and felt fine apart from bleeding. I rang EPU the next day and they asked me to go in for a blood test which I did and they confirmed HCG was where it should be so they were happy to see me for a scan at weekend. Went with DP on Saturday. The sonographer did an abdominal scan and said everything looked great, there was a strong heartbeat and the baby was measuring around 6 weeks or so. Straight away I panicked as - going off my LMP - I calculated I should be 8 weeks. After the scan we went in to see the midwife who basically said the same as the sonographer. Everything looked great (they couldn't see any cause for the bleeding so might just have been a one off) and that I won't be seen again until my 12 week scan.

I asked her about the dates as I assumed that meant I was measuring 2 weeks behind and she said I'm not - they go off the date of implantation (date baby starts growing) whereas I am going off the date of my LMP so yes, there'll be about 2 weeks difference. Can anyone confirm if this is correct?? Because going off everything I read on here the scan dating should be the same as where you think you're at weeks wise? Or am I wrong?

Any help / advice appreciated!

Yeah, that sounds weird to me. Weeks were always counted from LMP in any scans I had. Then adjusted after first full scan at 12 weeks. Certainly if LMP put me at 8 weeks and scan said 6 weeks I would consider that 2 weeks behind same as you.

I hope everything is OK.

The midwife is wrong. The sonographers use your LMP date (which is why I always had to lie about mine as it doesn't account for people who ovulate later than average). Do you know when you ovulated?

Thank you @TheBirdintheCave and no, I don't have a clue. To be honest I've never tracked ovulation at all. I don't get EWCM or a change in BBT?? My last LMP was 25/11 and I did the test on 24/12 (which was a faint positive) following a late period due the day before.

Also to add, I had similar happen to me in July, really they should be doing another blood test to check your hcg is doubling. Just knowing what your hcg level is isn't enough as they vary so much.

I did say this to the midwife and she said they would only do that if they had any cause for concern???

@Caffeinedetox I mean, any bleeding is a cause for concern surely?

I thought so! But no, apparently because there's nothing showing on the scan and it was a "one off" with no pain / cramps then they're not worried??

I can tell you about my experience but I don't want to be negative as mine ended in miscarriage, but more than happy to explain it if you wanted?

Well this exact same thing happened to me last time and ended in miscarriage a few weeks later (hence the worry!). But last time the midwife and sonographer were not positive at all and basically prepared me for the worst. However last time I did have an internal hemorrhage which was picked up on a scan so I was scanned regularly until I eventually miscarried.

But no, I would appreciate any experiences positive or negative. I am a realist and although I want to remain positive, I'm also prepared for the worst.

@Caffeinedetox

Ah okay probably a similar experience to yours last time then.

I had a bleed in the night at about 6 weeks, got up too quickly and fainted, rang 111 who sent me to a&e, which I wouldn't do again but there we are. They just did bloods and said my hcg was 5000 or something which was good, referred me to EPU for a follow up blood test, 48 hours later.

This went up but didn't double, so they repeated again in 48 hours, went up by didn't double, so had an internal scan (nothing showed on abdominal one) found a heartbeat but said it was a bit behind size wise.

Rescanned in 2 weeks I think? No heartbeat and then had to have another scan to confirm no growth or heartbeat.

They could see where the bleed was on the scan but never gave a reason for it, however I'm now pregnant again and my midwife has told me several times that no bleeding is ever 'normal' and should always be checked. Obviously people have bleeding and are absolutely fine so it can be normal.

At the very least they should be re doing your hcg test as the normal ranges are soooo big!

I'd take the heartbeat as a very positive sign.
DS1 was scanned at 6 weeks (no hb) and 8 weeks. He grew about 3 days in those weeks. I queried it, they had another look, and he "grew" another week or so in size in half an hour.
Baby is so tiny at this point, it only takes a slightly twisted angle, and the dates change dramatically.
I know the stress of not knowing, but honestly, the heartbeat is a great sign.

Thank you @SnowsFalling - that's what the midwife said. To be honest I should have asked more questions when I was there but she was so positive and nonchalant about everything I felt like I would be being a nuisance if I kept coming up with issues! I have my booking in appointment next week so will note down some questions to ask then.

Did they give you any paperwork at the scan that gives your estimated delivery date (EDD)? This should clear up whether they were saying the baby is 6 weeks old from conception/ovulation or 6w from LMP

Did they tell you how big the embryo was measuring, that might also help work it out.

@LavenderSweetPea Nope - nothing at all. Just a scan photo. They did tell me the embryo was measuring 3.5mm and that was consistent with 6ish weeks but that's all!

I didn't even mention about the HCG as they just seemed so flippant about everything that I felt like I was being over-paranoid! But I have my booking in appt next week so will speak to the midwife then. Having said that, if I am actually 8 weeks as I thought, then I've read (on MN obviously!) that your HCG starts to plateau anyway so don't think this would put my mind at ease!

3.5mm would indicate a gestational age of 4 weeks from ovulation, so 6 weeks by a standard 'add two weeks for LMP'. This is two weeks behind your actual LMP and suggests you ovulated later in your cycle

Thank you @LavenderSweetPea As I said in a PP, I never track ovulation so don't have a clue when I would have ovulated?? We have sex almost every day (or did up until I had this bleed and scared ourselves!) so conception could have happened any time really?? My first period after the MC was in August and my cycle then varied from 28-32 days each month until December when I got my BFP.

I do think it's odd though that if you ovulated and conceived 4 weeks ago how you managed to get a positive pregnancy test on 24/12. Is there any chance it was actually an evap on that test rather then a true positive? Did you test regularly after that to see them lines getting darker?

If your hcg is right for 6w, and you had a healthy heartbeat on the scan these things are far more important really than the dates anything happened, they'll be able to confirm dates better at your 12w scan anyway

The measurements and dates for both my pregnancies never seemed to match with my dates! This was true even when I had ivf so knew exactly how many weeks pregnant I was. The main thing you need to know is that they saw a heartbeat and everything looked fine. Take comfort in that. I'm sure it'll all be back to your dates when it gets to 12 weeks (which will probably feel like a year). Congrats on your pregnancy xx

Shame they didn't give you a copy of the scan report

FYI I have had 3 pregnancies (2 were MC) and they've never checked my HCG via blood. TBH I can understand why they might not if the scan shows a viable uterine pregnancy, but i am a bit surprised they haven't suggested a rescan in q couple of weeks.

I didn't have a blood with my MC either. Everything was completely different this time?! Despite being the same symptoms and the same timeline?? The only thing I could think was that it's because it's a different Trust so maybe different rules??

Thanks @LavenderSweetPea I'm assuming I ovulated mid December?? My last period was 25/11 and I took the test on the 24/12 (29 days from my LMP) and got a clear positive. Yep, did a couple more tests the week between Xmas and NY and both were darker than the previous...

I’m afraid my experiences of the same didn’t have good outcomes either.

However, at the time, when I was on here looking for reassurance, many others wrote that they had the same with a good outcome.

With our successful pregnancy EPU prescribed progesterone, levothyroxine and baby aspirin. To take immediately on positive pregnancy test. I also had fortnightly scans.

Are you in the U.K.? Your EPU should have prescribed progesterone for you to take because you have bled. The NICE guidelines changed, women who bleed during their current or a past pregnancy should take progesterone.

^^ yes good point @RippedJeansAndCashmere

I was dated by fertility clinic and although I had ivf , they still used date of my LMP . midwife and private sonographer both dated me aswell using LMP.
If they dated based on actually conception , because I had ivf I'd be weeks ahead which wouldn't be right at all