Q: 1st Tri Screening for Twins

4legsRbest

I know this has been asked before (but I suck at searching on TB) so I wanted to ask again since all the posts I found are 2010 or older and science moves forward every day.

We are scheduled with an MFM on Monday for our 1st tri (NT/bloodwork) appointment. My last pregnancy was a singleton and it seems the rules are different with multiples. I have done some googling and what I am hearing is that the blood tests for 1st tri are out with multiples (Mat21, Panorama, etc.) and that a CVS or amnio is the only way to go if you want any results. Has this been your experience? I am over 35 and IVF but nothing else points to a high risk for genetic disorders based on our history, I have just naively assumed to this point that the test would be the same as with my DS. If a CVS or amnio is our only option, DH and I need to discuss prior to Monday and this has never come up before so it isn't even on our radar. Just don't want to be blindsided by the counselor.

Any advice or experience is appreciated!

daisy19782011

I have twins and did the materniti21. There was only 1 lab that runs it for twins in my area.

4legsRbest

Oh thanks Daisy! I know I will have to wait and hear on Monday, but what I had in my head is different that what google is telling me is possible.

carrotcake06

Are your twins di/di? Mine are and what I was told is that you can do the typical first tri screens but that they are only 80ish% accurate or something. I was not offered any of the "new" blood tests - mat21, etc. I was offered a cvs by virtue of being almost AMA for twins. Ultimately, the first tri screens (and 16w quad screen) came back w low risk so we opted out of the cvs. Had something come back higher risk we would have crossed that bridge of additional testing but since all signs pointed to healthy babies, we declined the cvs.

4legsRbest

Yes @carrotcake06 they are di/di. I went to Sequenom's site (they make Mat21) and they do say that the test is accurate for multiple fetal pregnancies, but that they can't report on sex aneuploidies in multiple gestation pgs, which is fine, becuase those do nothing to affect the ability of the baby to live.

I am AMA so I am wondering if they will want to go the CVS, route. I don't think I will do that one though but I know virtually nothing about it at this point.

This is what the ACOG has to say about it (below). So even if they do serum tests (any of them), the accuracy is in question. I may just leave well enough alone and let this one go. I really wanted to do the screening, but not if the accuracy rate is poor.

Data on multiple pregnancies with one aneuploid fetus are limited; therefore, when performing screening tests, analyte levels must be estimated. Additionally, analytes from all the fetuses will enter the mother's serum and will be averaged, which could hide the abnormal levels of the aneuploid fetus. Therefore, serum screening is not as sensitive in multiple pregnancies as it is in single pregnancies. Counseling also could prove more difficult because women who are pregnant with one or more normal fetuses and one aneuploid fetus have different screening and diagnostic options. Until further evaluation is performed, assessing risk in multiple pregnancies should be done cautiously.

ETA: typos

lynnyrd80

We did the NT scan and blood work for our twins and nothing was said about needing a cvs or amnio.  They were able to look at the nasal bone for each baby and measure the fluid behind the neck.  We got our risk ratio or downs based off of these numbers.  I'm not sure how the blood work affected the numbers since we got a different ratio for each twin.

They did offer us the panorama, but we chose not to do it.  I think the only thing it couldn't tell you was a definitive answer on the sex of the babies.  They can tell you if the twins are girl/girl or if you are having at least one boy.

ExcitedKJ

A friend was able to have the Harmony blood test between 10/12 weeks and I've looked it up and plan to check on it next week with my OB consultant. So, maybe it's an option in your area

Ylvelill

My ob said only the mat21 test works for twins of the newer tests. We had that done and the NT scan/bloodwork.

The mat21 test won't be able to give you results on the sex of the babies though.

mer313131

I was told (by my old OB, I'm switching) that the mat21 is not covered by most insurances bc it is considered experimental for twins. I'm also AMA when I deliver so I was a bit surprised. He said it would be $850.

pillowass

I was also AMA (barely - 36) with IVF di/di twins. We had them check the nuchal fluid on both twins around 12 weeks. Since that was good and there were no other concerns, we chose to forgo the more invasive testing. We were told that mat21 wasn't accurate for twins but this was a few years ago.

Ylvelill

The mat21 test is $200 if you have to pay out of pocket, just call them if there is an issue.

4legsRbest

Ylvelill said:

The mat21 test is $200 if you have to pay out of pocket, just call them if there is an issue.

Yes, I hear they will cap it at $200 if youare OOP on it. I mean, I am laready over 60k into IF related expenses, what's another 200?

Thanks for all the feedback!