Genetic Testing in Twins

At 12 weeks, we were referred to a maternal fetal medicine practice by my OB. It was explained to me that because I was pregnant with twins, I was considered high risk. I was told we’d have double the appointments of a singleton pregnancy, but the silver lining was that we’d see our babies at every appointment.

At our first MFM appointment, the peri neonatologist mentioned at the end of the appointment she would have a genetic counselor come speak with us. It was standard.

The counselor asked Phil and me about our family history. The counselor told us we were not at a high risk for having a baby with a chromosomal abnormality.

The genetic counselor told us we had 3 options for genetic testing: 1. Not do it at all. 2. A quad screening (just tells you if your baby is at risk for a trisomy or has a genetic condition such as spina bifida) 3. A cell free DNA test. 

We decided to pay out of pocket for the cell free DNA test. The company that offered the test is based in CA and boasted that they were the first to be able to conduct cell free DNA test for twins. The counselor said that the test would also tell us the sex of our babies. I went to the lab at MFM’s office to have my blood drawn. The phlebotomists looked at the test and said “Wow! This is a different one than I’m used to,” she said, examining the box.

“Yeah, this is the only company that has the technology to run this test on multiples.”

“Oh! That must be new! I haven’t heard of that.”

I knew that I’d have to do wait 7-10 days to get the results. Day 7 came and there was no call. I started to panic. Day 8 and 9, still nothing. Day 10, nothing. I called the genetic counselor and she said she’d look into it. 

She called back and said there was a delay with the lab. 

I know after this conversation I had a dream that we found out that we were having a boy and a girl and that both babies were healthy. You’d think that would put my mind at ease, right? Well it didn’t.

I believe on day 13 I got a call from the counselor. The lab said they wanted to re-test because there was something wrong with my blood sample. The counselor said it could be anything from a lab error to not getting enough fetal dna. 

I let my mind go to the worse outcomes. I was terrified that both of my babies had something horribly wrong. It couldn’t be something simple like my blood sample getting hemolyzed. 

I went into the lab the next week to get my second sample of blood drawn. By this point in the pregnancy, I felt like I knew all of the phlebotomists in the lab due to all of my prior “routine” twin tests. “You’re back!” a phlebotomists said.

“Yup! The other lab messed up my sample. I need to re-test.”

“Oh shucks. Don’t worry. I’ve heard of people accidentally dropping samples. Human error... what can you do?” 

“Human error? Could someone have just simply made a mistake or had a minor accident? Sure. Sure, that was it,” I thought.

“No, no, something is wrong. I couldn’t be lucky enough to have two healthy, normal babies.” Per usual, my mind went to the darkest places.

I tried to not focus on the genetic testing and just enjoy being pregnant over the next few days, but I couldn’t.  My 2nd blood sample was sent away and I was left with another 10 day wait. The agony! 

On the 11th day, the genetic counselor called and said “Well, I don’t have great news. The lab said there was an uninformative DNA sequence and they don’t recommend retesting.”

My mind raced. My hands felt sweaty. I could feel a lump in my throat as I tried to not cry.

“What does that mean?”

“Well, it means that they don’t recommend re-testing because they think they’ll get the same result.”

“So why would I get this result?” 

“Well, it could be anything, but there’s a good chance your babies are normal.”

I didn’t understand any of this.  I called my husband in a panic.  Phil calmly said, "We don't know anything yet.  For all we know, we have two healthy babies."  To this day, I'm not sure how Phil could be so level headed throughout this ordeal.  Maybe I worried enough for the both of us?

The genetic counselor scheduled an appointment for us the next day at 7:30 am to speak with her and told us we could get an ultrasound with an MFM doctor and opt for an amniocentesis. The amnio was the only thing that would give us the answers we thought we needed.

It’s funny how sometimes people just “show up” when you need them. My cousin’s wife, Natalee, is an ultrasonographer and a mom. She texted me that evening when I was all worked up. She asked how I was doing and I just laid all of my emotions on her. She asked if she could call me later and I said, “absolutely!” 

When she called, I heard the calm in her voice. I needed the calm. I explained what was happening and how I was freaking out. She said, “Ok, now you’re 16 weeks pregnant and you have had multiple ultrasounds. If your babies had trisomy 13 or 18, they would have seen it by now. Little Down syndrome babies typically can be detected by ultrasound, too. A lot of times they have little heart defects.” She went on and told me some other signs and mentioned how they’d measure their necks in a few weeks.

I breathed a small sigh of relief. “Ok, they most likely don’t have trisomy 13 or 18,” I thought. 

“Are you sure you want to do an amnio?” Natalee asked.

“Yes, I just need to know,” I said.

“Are you aware of the risks involved? I know they’re uncommon, but amnios can be risky.”

I was aware, but hadn’t really had time to process the risks.

“I’d suggest going to the ultrasound tomorrow and see what the doctor says. Just remember, there’s a lot worse things that could happen than to have a baby with Down syndrome. They tend to be such happy kids. If you must have answers, I’d suggest waiting until you’re farther along so if something does happen and they need to deliver the babies, they’d survive. Wait at least until 28 weeks.”

Part of me knew Natalee was right. 

My husband and I discussed the risk of the amnio. I told him what Natalee had said about how trisomy 13 and 18 probably would’ve been detected by that point. That left Down syndrome.

“Look, Caiti,” Phil said, “I’d much rather raise a baby with Down syndrome than risk one or both babies’ lives. It’s up to you, but I don’t think we should do the amnio. I know you’d never forgive yourself if something happened.”

I couldn’t sleep that night. “What if something is wrong? Can I be a parent to a special needs child?”

I can’t remember a lot do the conversation with the genetic counselor, but I do remember her mentioning that we could be getting this result due to a mosaicism or it could be possible that there was still some DNA from the miscarriage I had two months before I got pregnant with the twins. 

Mosaic Down syndrome was brought up. She explained that mosaic Down syndrome is when there are a mixture of cells with two copies of chromosome 21 and some with 3. 

“This has to be it,” I thought. “One or both of my babies has mosaic Down syndrome.” 

After speaking with the genetic counselor, I felt more anxious than calm. She did not calm my fears, she just made me think of more things that could be wrong with my babies.

We went in for the ultrasound. The ultrasound tech was amazing! She just kept reassuring me how normal my babies looked. She then said “I’m close to Baby A’s parts. Do you guys know what you’re having?!”

“No, we don’t know yet.”

“Do you want to know?”

“Yes!!!”

“Baby A is... a girl!” 

I started to cry tears of joy. Finally some news that wasn’t scary. Just news.

She finished up measuring sweet baby girl and then moved onto Baby B. I’m sure she could tell I was anxiously awaiting the sex reveal. It was very obvious what Baby B was. 

“And Baby B is... a boy!” 

Phil said, “Now that’s a grundle!”

I laughed. More tears of joy! I looked at Phil and for the first time in weeks I just felt happiness.

The doctor then came in. The doctor I needed to hear from. She was calm and informative. She offered us gentle guidance. She said, “So you guys want an amnio?” 

I explained the inconclusive results and she said, “Yeah, genetic testing is just super tricky with twins. In fact, this practice is going to stop using that test. We can do an amnio, but it’s risky. It’s riskier with twins.”

I immediately thought “Nope, this is not what we’re doing.” Phil was on the same page. 

“I have a good track record with amnios, but you should know that there’s a chance I could end up getting the same sac twice instead of the other sac. There’s also a risk that it could cause a miscarriage. There’s also a risk of infection.” I just knew this was not for us.

“What are you hoping to gain from the results?” the doctor asked.

“I just want to know if there’s something wrong.”

“Ok, what if there was something wrong? Would you want to terminate? I think you should know that in the state of Utah, selective reduction is not legal.”

Selective reduction is when you abort one or more fetus in a multiple pregnancy.

The doctor went on, “You’d have to go to either California or Oregon to have the procedure done.”

The doctor went on to say how normal both babies looked and we decided that’s all we needed to hear. 

I knew that I could not risk the lives of my babies and terminating my pregnancy was not something I would do, regardless of whether or not one or both babies had a chromosomal abnormality. 

Because I tend to be a worrier, I still expected one of my babies to be born with special needs. I kept seeing videos on Facebook with children with Down syndrome being suggested for me to watch. I felt like it was a sign.

I watched the videos and saw their smiling faces. I mentally prepared for a baby with Down syndrome. I kept this a secret from everyone... even my husband. 

Each ultrasound that followed, I fully expected an ultrasound tech or the peri neonatologists to notice something wasn't quite right.  Appointment after appointment, we just kept hearing how incredibly normal our babies were.  

I was relieved to always hear such solid heartbeats and to see little limbs moving around.  I tried to push negative thoughts out of my head and just marvel at the life that was growing inside of me. 

When the twins were born, I stared at them with wonder but also checked for some physical markers of Down syndrome. Neither of them had any. 

“What?!” I thought. “How can this be?”

I sat in the hospital looking at my new, precious babies and felt like some of my joy was stolen from me during my pregnancy. Instead of being consumed with thoughts of how wonderful it would be to have my twins, I spent a lot of time wondering how hard it would be to raise a child with special needs.  I spent a lot of time wondering why we got inconclusive results.   

I think genetic testing with twins has not been fully fleshed out. I googled and googled my results from my cell free DNA test and I was not the only person who got the same results. In fact, there were many twin moms that were in just as much of a panic as I was.  I think the company that makes this test should not market it. I don’t think this test should be offered to twin moms.