Chromosome Testing

[scarvesandhoney]

We just found out this week that we are expecting twins! With our son, we did the MaterniT21 testing to rule out any chromosomal abnormalities. Do you know if there are any similar non-invasive tests that can be done for twins?

[Squishy622]

Congrats! We did MaterniT21 with this twin pregnancy. They'll do it and both the company and my docs agree that its valid, though it hasn't yet been actually published in the literature as such yet (my MFM expects this in the next year or so).

The big sticking point is that if there is an issue, you may not be able to tell which twin it's with, especially if you know they're fraternal. Same with the sex- it'll tell you if there are 2 girls (absence of male chromosome), but unless they're mono/di or mono/mono, if the male chromosome is there you won't know if one or both are boys.

All this to say, I'm so glad we did it, and had anything come back abnormally we would have used it as a decision making tool for more invasive testing like amnio or cvs.

ETA: I'm glad we did it because we saw some potential Trisomy 18 markers on u/s at 16 weeks and the NIPT is much more accurate than u/s. Having the M21 results for the 2 weeks I had to wait for that follow up u/s and the peace of mind that gave me was priceless.

[scarvesandhoney]

Squishy622 Thanks for your advice! I think we'll go ahead and do it for peace of mind. I'd rather have that knowledge and be able to proceed with more advanced testing if necessary. I am completely neurotic, so hopefully I'll feel better.

[Squishy622]

No problem- hope you'll stick around and join us here. Good luck!

[thesportsgal]

I wish I would have pushed for it but my doc didn't want to do it, basically for the reasons Squishy622 said. She would have pursued it had something shown up on our NT scan but we didn't. So the NT scan was the only non invasive test we did. Best of luck!!

[snd1231]

I looked and from what I saw Harmony and MaterniT21 both will do the test on twins but not anything more than that. Panorama will not do the test on twins. But that was just google research.

[Squishy622]

Jun 11, 2015 18:22:34 GMT -5 snd1231 said:

I looked and from what I saw Harmony and MaterniT21 both will do the test on twins but not anything more than that. Panorama will not do the test on twins. But that was just google research.

This is true, however Harmony doesn't report the sex on twin pregnancies at all so if you're hoping to learn that info, go with M21.

[schmella]

We did CVS, because we needed to know which results were which. If time wasn't a factor, we would have gone with amnio as its lower risk, but we needed it done by 12 weeks. FWIW, it wasn't painful, just uncomfortable, and if you end up having to do it, find someone who has tons of experience.