Does it matter how close to 20 weeks you have the anomaly scan?

(16 Posts)
BettyBi0 Mon 16-Nov-15 13:14:21

Does it matter how close to 20 weeks the scan is done?

After having some worries at my 12 week scan, I'm now impatiently waiting for the 20 week scan to see if my baby is healthy or not. It's a worrying time as although my harmony test came back negative, there is still a strong possibility of other chromosomal issues due to rubbish bloods at 12 weeks. My NT was only 2.6 so they were happy to offer me basic screening via CVS for Downs based on my bloods, but not the full chromosomal profile as NT was only borderline. We opted for the harmony test instead of CVS bit I'm still worrying myself sick about the other possibilities.

My anomaly scan is scheduled for when I'm 20+6. Should I be pushing to have it earlier or is there a window for accuracy like the 12 week scan at 11-13 weeks?

I'm also worried about cutting things fine if God forbid I need a TFMR.

OP’s posts: |
PotteringAlong Mon 16-Nov-15 13:34:28

Unless I've misunderstood then if your harmony testt was negative then there is no problem?

LastOneDancing Mon 16-Nov-15 13:41:41

Have you discussed this with your midwife? I'd hope she can tell you why it's set at 20 weeks and if they can bump you forward.

Is it possible for you to have a private reassurance scan? They will do the full run of checks that you get at the hospital IIRC.

Hope all is well OP.

KittyandTeal Mon 16-Nov-15 14:25:01

I'm sorry you're worrying about this.

The closer to 20/21 weeks the better. I had 2 anomoly scans, one at 19 weeks and one at 21. My 19 week scan all looked fine and we were told sex.

21 weeks the heart and brain were easier to see and abnormalities (T18) were picked up.

I had a tfmr at 22 weeks. You are allowed a tfmr up to term but there is an additional element after 21 weeks. Even at 20 weeks, you'll need to wait 2/4 days for rapid results (that would have been picked up by harmony) and up to 2 weeks for full kayotype. I'm really surprised they didn't offer full karyotype for a cvs. That's a bit off.

I think 20+6 is a good time for an anomoly scan.

Have you contacted arc? They're very good while you're waiting for results or worried.

KittyandTeal Mon 16-Nov-15 14:27:17

Pottering the harmony only tests for T13, T18 and T21. There are lots of other chromosomal abnormalities that can be lethal/incompatible with life. That's why I'm surprised the op hadn't been offered a full karyotype

PotteringAlong Mon 16-Nov-15 15:13:02

Sorry kitty, I was wrong. And I'm really sorry for all you had to go through.

flowers for you and the op

KittyandTeal Mon 16-Nov-15 15:47:29

Sorry pottering, I hope that didn't sound 'snotty'. It's just I've realised recently how little we all (until you go through it) know about chromosomal abnormalities. Until after I had dd2 I also thought the harmony test was fully diagnostic.



SummerHouse Mon 16-Nov-15 16:05:01

I went through something with some similarly to your circumstances op. I have never been so terrified I actually had the runs for weeks on end (TMI)!

You can do this. Be as brave as you sound. Don't know what to say about the scan. I feel like you probably need to wait in order for it to be as effective as it can be and as reassuring as it can be.

SummerHouse Mon 16-Nov-15 16:05:38

Everything crossed for you. flowers

PotteringAlong Mon 16-Nov-15 18:28:54

No, it didn't sound snotty at all smile

I'm grateful every day that this is an area I don't know much about. I'd much rather be told so i don't make the same error again.

KittyandTeal Mon 16-Nov-15 18:42:37

Oh good, it's so hard to convey tone online smile

Alyselisabeth Tue 17-Nov-15 17:42:13

Hi. The closer to 20 weeks the more you can see. I had a scan at 17 weeks which was all fine. Everything looked ''normal''
20 week anomaly scan showed multiple anomalies, resulting in an 'incompatibility with life'' diagnosis.

I know how hard it is to wait and how desperately you want the time to come just for reassurance but it really is best to wait xx

Lozza1990 Tue 17-Nov-15 17:44:56

The earlier you have it the less accurate it will be, so it's probably a good thing that you will have it later. I know it feels like forever just hang in there x

BettyBi0 Thu 19-Nov-15 09:13:50

Thanks so much everyone. It's so hard waiting but I know now that I'd rather not have the scan earlier and be falsely reassured.

I'm trying to concentrate on the "every reason to be hopeful" line of thinking as my NT wasn't bad just the bloods. But it's pretty hard keeping a lid on it all.

OP’s posts: |
Wikkitikki Wed 19-Oct-16 07:58:35

I know this thread is old but I had scans at 16weeks with the fetal care unit in my 3rd and 4th pregnancies after a TFMR in my 2nd pregnancy. My last pregnancy was in 2005/06 so this is information I was given at the time.

At the 16 week anomaly scan they could rule out Spina Bifida and assured me that nothing abnormal was detected in the brain but the 20 week scan picks up more heart defects(but not all) so I was told.

DollyBarton Wed 19-Oct-16 08:00:33

20 weeks is the cross cross point between baby being developed enough to see their systems in action and just about small enough to get a scan.

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