Saturday, March 29, 2014

And, Even More on the Unreliability of Ultrasound Measurements During the First Trimester

Over the last week, I've blogged a bit on the unreliability of ultrasound measurements during the first trimester.

Women have shared that they have had two different ultrasounds the very same day by two different techs and measurements have been quite different. 

I've also pointed out, that this discrepancy in numbers has also been noted.  In the article Does Ultrasound Sometimes Misdiagnose Miscarriages on WebMD, they had this to say:
"The fourth study explored the accuracy of ultrasound measurements when repeated by the same doctor, and also by a different doctor. Although the repeated measurements were largely similar, there was enough variation to raise concern - particularly when the measurements were close to the cut-offs used in guidelines to diagnose miscarriage. For example, if one doctor measured the sac as being 20 millimetres in diameter, the range for the other doctor’s measurement varied from 16.8 to 24.5 millimetres."
In pregnancy a difference of 4mm can 'make or break a pregnancy' from a physician's point of view.  If the sac *looks* too small,  they can diagnose a miscarriage and try to push a D&C.  We see that all the time on the Misdiagnosed Miscarriage site.

So, this week when yet another mom posted that her pregnancy was being doomed (chromosomal abnormalities, miscarriage) based on the measurements of the yolk sac, I cautioned her to take that information with a grain of salt.  I'll post more on the 'yolk sac scare' in a future post.  Just in a nutshell, we've had women report being given little to no hope based on yolk sac measurements and their babies were just fine.

After continued prodding to have another ultrasound scan, everything was measuring just fine.  In fact, the ultrasound tech rechecked the previous ultrasound photos, did measurements on them and, you know what happened, she got different measurements off the EXACT SAME PHOTOS.  The measurements had been completely normal and almost half what the first tech had said!

Moral of this story?  You can take the exact same ultrasound photo and two different techs can get two different measurements.  Don't stress the measurements.   There is a really good chance that no matter what measurement you get, it's off.

(((hugs))) to anybody going through a miscarriage scare right now. 


  1. Very interesting Kay.


  2. Thank you. This was EXACTLY what I needed. My DH and I just came from the midwife and as per my LMP I'm at 9 weeks. Didnt see anything in the sac (even went to the radiology dept for the TV scan). Midwife called to say the sac measured only 7w2d and to come in for bloodwork because it looks like a chemical pregnancy. This really gave me hope.

  3. I want to share my story because this happened to me just yesterday. when we found out we were pregnant four weeks ago as we were away from home, DH and I found a gynae online and we visited her twice. Second visit at 5weeks we could see a sac but nothing inside. she scheduled a visit three weeks later and she still couldn't see anything inside the sac and it measured slightly bigger than at week 5. she told us its a blighted ovum and we should schedule a D&C. I told her I would like for it to happen normally. We told my husband's family about the miscarriage because we are visiting his home town and they are really close. At this point only our mother's knew. We went to a family friend who is a gynaecologist this afternoon and he did a transvaginal ultrasound and the sac was not empty and we heard a heartbeat. I bawled my eyes out. I am so glad we got a second opinion.. hoping that we go on to have a healthy baby. I am 35, DH is 37. this is our first

  4. Oh my goodness, congratulations! I am so glad you got that second opinion. Wow! Would you consider sharing your story on ? If you'd rather, I could post it for you if you just come up with a name (doesn't have to be your real name). Thanks!

  5. I just want to share my own story. I had my 8 weeks scan on Saturday whereby the doc didn't even measure the sac or even do a blood test. He just told us its empty so it happens and blla. I was in shock because this is my 2nd baby and and this didn't happen with my 1st baby. I was tuned off and in tears but my husband managed to tell him we would wait a week. We got home spoke with my mum and we decided withing ourselves to wait 2 weeks. I however went to another hospital. Did a BPT yest and HCG test and was told my BPT test is positive and the HCG levels are raising in order. I have been so distraught and unhappy for the past few days. I have prayed and I know my baby will be seen in 2 weeks. Thank you so much for your post this has given me a light heart this night.

    1. Keep us updated! You were diagnosed too soon. I hope you get better news.

  6. What a great venue for women who are going through similar experiences. Pregnancy can be an exciting time, yet scary if you don't know what's going on or in a limbo! We used ovulation sticks to conceive, and my LMP put me in 7 weeks 6 days for my first ultrasound. It was the most confusing experience ever. The ultrasound tech showed me a flickering heart and a fetal pole with abdominal ultrasound and I was so excited. Then when she did a transvaginal, she was trying to measure the heart rate but was silent after that and took a bunch of pictures for the radiologist. The radiologist came back saying that it was too early to detect anything, no fetal pole. So i guess the tech was inexperienced? The second time i went after 2 weeks and the ultrasound just showed gestational sac and yolk sac, no fetal pole. I went to see an obgyn doc the day after, and she saw a fetal pole measuring 6 weeks, no heart beat. although i was excited to see fetal pole, i was bummed out that it was only 6 weeks... according to lmp, i should have been 9 weeks by then... anyway, tomorrow i'm going in for another ultrasound to see if the baby grew and has a heartbeat... should i be hopeful? now a days, i'm sick of all these ultrasounds and just want to know what's going on.....

  7. Reading all these posts lifted up my spirit. I went for a scan last week, Doc didn't see any baby (from the computation, I am 8 weeks) and said I had a miscarriage. Husband and I was so confused as i did not have any bleeding at all. She gave me tablets (cytotec) and wanted to schedule me for a D&C we protested and ask if we can have a transvaginal ultrasound. So off we went and the technician said it is still too early and adviced us to come back after a week (longest week of my life!) Also had my HCG done and came out, 64000 which my specialist said they are good numbers. Anyway, went in for another ultrasound today, sac was there but still no baby. Doc said the embryo did not grow. So husband and I went home with heavy hearts but we decided to get a second opinion tomorrow. And after reading all the posts here gave me hope that the baby is just hiding. And that we will see him/her soon. Wish me luck! xx

  8. Hello
    I went to doctor for my 8 week check up. They saw baby and heartbeat 157 but said my yolk sac measured a little big. I was suppose to be 8 weeks 2 days but baby measured 7 weeks 5 days. Sono tech said that was ok since my period was 32 days that month. They are sending me to a specialist in 3 three week. Has anyone be told they have good heart beat and slightly large yolk sac? I am also 36 and this is my third baby.


  9. I was scheduled for a D&C on a Monday, but my body told me to wait it out. My doctor said there was NO WAY I had a baby in there... and there was definitely a baby in there!

  10. hi..I was having somewhat similar experience as of the others. I got pregnant for supposedly my first baby but sad to say i had a miscarriage on the 10 week. I was devastated though i just recognize i was pregnant on the 8 9 weeks maybe. After a month I got miscarriage d, I get pregnant again. So, my my husband and I went to my OB Ggyne. She told me to have a Transvaginal ultrasound on the 8 weeks of my pregnancy. The US result result shows that I have a twin babies but the don't have a heartbeat. I immediately went to my OB and she advice me to have D & C, and gave a medicine for ripening of cervix. I went home very very sad and cried to my husband. I told my family about it and the advice me to seek for a second opinion. I also told my friend bout it. And told she had the same diagnosis with her 3rd child and she was requested by his OB to have a D & C but she refused to do it. And have a second US. And result shows it has a heartbeat. That is why I had the the chances left. I went to another Gynecologist and show her my US result. And she told me that she do not immediately recommend a D&C instead she give a med and vit to help me. And given me a request for another US. She told me if had some spotting I should immediately have the US but If not I should have to wait for weeks and told me that on the second time around the babies should have a heartbeat. And I a praying that God would have miracles for my twins. I have a strong belief and Faith in God's miracles. I know He is listening with my hearts desire. Thank you for this site I can say what my mind and hearts says and desires for .

  11. I'm going thru this , I started spotting 13 days ago went to a and e waited for a scan . The scan show a sac and it measured smaller but they never said by how much , at the time I was convinced of my dates cos I know when my monthly started but I read you can ovulate at different times is this true can you ovulate later in you cycle? I don't really know , hate hcg test over 48 hours told it should of doubled but it rose a bit ? I have another scan in two days . I've read so many stories , my spotting lasted 9 days never reached the pad ? Been told my pregnancy isn't viable , I grieved at first but now I pry i have my dates wrong some how , advice welcome please

  12. I am going thru something very similar. Last week I went in to see my OB/GYN for the first time since finding out I was pregnant. My periods are irregular sometimes coming late sometimes early. My last period was at the end of December so I got pregnant sometime last month. My HCG level went from 5,300 to 9,900 over the course of 5 days. My OB/GYN said thats too low. I had a repeat U/S done a week later and still just an empty sac and only a very slight change. Keep in mind I have a inverted uterus as well. I was told today by my OB/GYN that he was sorry for my loss and I can wait for my body to do its natural course or can consider other options. We am devastated as this is my second loss back to back. FYI I have no symptoms of a miscarriage. I pray there is hope.

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