Chances of due date at 10 weeks via ultrasound being incorrect?

[BabyCakes]

Dear All,

I am so confused about the outcome of my dating scan which is +5 days of my calculated date.

I am sure I ovulated on day 17 and with the new date, it would shows a conception day on day 12.

I am absolutely sure this is incorrect as my cm and opk all correlate with day 17.

Can anyone explain how this could be true or if the scan could be wrong?

The baby measured 38.2 and that correlated to 10 +5 weeks. This cant be right! or can it?

Thank you!

[atomic sagebrush]

Well, with a skilled tech the odds are slim that the ultrasound is wrong, BUT real world applications, sometimes the tech sucks, they are tired or hungover or hugry or they have to pee and so you have to take it with a grain of salt.

CM and OPK are great, but you have to view them as tools and not guarantees. When I got my daughter I had EWCM after ovulation and I know of several people who got pos OPK that didn't seem to correlate with ovulation.

Is there a reason why you're concerned (such as you think it may have messed up your sway) or are you just curious?

[BabyCakes]

Thanks Atomic!

I am pretty sure, she was focused when measuring. She did it 3 more times to reassure me but it kept measuring a tiny bit bigger?? So I feel she was diligent.

I am more in absolute denial that this is possible because on the day that I would have "conceived", I had no CM, and for 2 days after, also little or not fertile CM, so I just cannot see how thats possible to have ovulated then as a 5 days later I had plenty EWCM and +opk..... I was tracking my cycle for over a year and I just cant see how these dates could be accurate??

If its true, my sway will be better though!! as I had multiple BD's around my calculated O, and only 1 BD, 3 days before this "revised conception date".

Just as an FYI, I think I am having a boy regardless....according to Ramsey (which I really believe the accuracy).

Your thoughts?

Thanks as always xoxoxoxox

[nuthinbutpink]

I think the only way to KNOW when you ovulated is to have scans done! The u/s could be a little off though...each baby is different of course and they work off averages.

[atomic sagebrush]

Because about that point after ovulating, your body has something called "the secondary estrogen surge" where you may see a positive OPK (false pos) and also EWCM, because your body releases a big burst of estrogen to maintain the uterine lining long enough for a pregnancy to occur.

[BabyCakes]

Thanks Ladies! I really appreciate the responses because I am a fertilityfriend tracking addict and I just cannot get over what this due date means..... I ovulated with no CM and a negative opk. Its just so crazy to take in that I was so off!! I wrote notes everyday and watched everything like a hawk for a year!

- note to self...watch out for the sneaky eggs popping out like under cover agents ;)

[maidentomother]

Can you post your chart?

[atomic sagebrush]

I also got pregnant with absolutely no visible CM one time. I was checking my pH 2-3 times a day and never saw one iota of EWCM and my pH never went up till I was already pregnant. Let me tell ya, I was SHOCKED at that ultrasound (because I was 3 weeks off what I thought I should be!) I was like "I thought it would look like a fish, but it's already a cute little baby" and the tech was like "uh, I think you're a little farther along than you think you are".

[maidentomother]

I have Oed on CD5 (and conceived a healthy baby to my knowledge) with no CM at all. So it's totally possible.

[maidentomother]

Another thing to keep in mind is that we typically only observe CM when there's enough to make it down to the vaginal opening. But often, despite being dry or seeing only non-fertile CM, there will be some (potentially fertile) CM right at/in the cervical opening, which is all that is absolutely necessary for conception. Since being on Vitex for most of the past year, I have discovered that despite seeming totally dry or only having a bit of creamy CM on my panties, often when I feel my cervix I can tell there's a fair bit of EWCM as it feels like loose jello/very thick EWCM. So I know now to never assume based solely on what I see when I wipe. Prior to Vitex and the LE diet I always had so much CM - whether creamy, watery, or EW - virtually all cycle long (except for a few to several days after AF, that's the only time of my cycle that I've always been dry, even in my teens & 20s), that I never thought to check at my cervix.

[atomic sagebrush]

:agree: exactly!!!

[BabyCakes]

Thanks so much ladies. I really appreciate the in-depth information provided. It really helps explaining CM. GREATLY appreciate your time :)

I went to the Dr this week for the nipt (harmony) test and explained my doubts on the dates and why and so they are going to repeat the dating scan next week just to appease me! I will update you all- but fully understand that it is possible to have Oéd and not known and had nothing correlate with it BUT, I just want to make sure they didnt make a mistake because it affects when I HAVE to take mat leave.

I really appreciate you all.
xoxoxoxo
Thank you

[maidentomother]

That's great! I hope the dating scan goes well and you get your NIPT results back soon. Fx you hear healthy & pink. :)

[BabyCakes]

Hi Ladies,

I went for my follow up scan today and it was the same +5 days on my dates!! You were right!!

The tech said, "OR, it could just be a big baby" but both my children were born at 3.2 kgs (7lbs) so I think that would be weird. I thought that was a silly thing to suggest if dating scans are supposed to be accurate?

Your thoughts?

[atomic sagebrush]

I think the techs try to humor people - they know that their numbers are right but people do get highly invested on when they get pregnant - for a variety of reasons, some of which are a bit shady LOL (as in, baby daddy, not you obviously babycakes, but some people) and so they say stuff like that to mitigate any potential conflict.

[maidentomother]

Agreed!

[2blue1pink]

We are pretty positive of our dates (had ultrasounds early on that were 2 days behind, then right on exactly, including at a perinatal center by a sonographer for high risk pregnancies). Yesterday my nurse practitioner snuck me in for a quick check on the baby since I had a m/c a few months ago, baby measured the days ahead, I should have been 10w5d and was measuring 11w1d. They definitely won't change my dates on that but it is really normal for ultrasounds to be a couple days off. I have had a lot of ultrasounds in all of my pregnancies due to being high risk and in my experience the most accurate ultrasounds have been at 8-9 weeks. Before that, the babies have measured a couple days behind. And after that, they usually measure a couple days ahead. (DS1 was already a week ahead by 13 wks-by a high risk sonographer- and we were pretty sure of dates because we had done IUI.)
I would try to get them to stick to the date you think you ovulated if they will!

[atomic sagebrush]

The later in pregnancy, the more variation that sneaks in and the more likely it is to be off.