MaterniT21 after vanishing twin

AlmostWright

We got our results back this week and baby is a healthy boy! We are so happy! But after talking to the doctor, I thought about us having a vanishing twin and wondered if that could affect the gender results? Blood was drawn at 12w3d, and the 2nd sac was basically absorbed by 7w, not seen at 8w. DS is also 4 years old, but I am assuming that wouldn't affect the results. We are thrilled either way, but I am second guessing telling people its a boy. DH wants to tell and I am driving him crazy second guessing. Anyone have any knowledge or experience with this?

PurpleIris30

Yes, a vanishing twin can impact the gender results, but I don't know if there is a gestational cutoff. I would call sequenom directly and ask.

Roeni

I was in the same situation, but if they found male chromosome in your blood then it's probably right. I had twins until 8 weeks and got a similar test called the ultrascreen around 13 weeks. They told me I was having a girl, but at my 20 week screen I learned I was having a boy.

becomingmommyagain

I did Materni21 at 10w3d and had to repeat at 13weeks due to insufficient fetal DNA.  I would doubt that a vanishing twin at 7 weeks would affect the test given that my singleton wasnt producing enough fetal DNA in my blood at 10 weeks.  But you can surely follow up with the testing agency for specific details.