Anybody know how accurate the genetic blood test is?

Ca

I keep hearing that the blood test to find out gender isn’t reliable, especially when I was considering Sneak Peek. I’m measuring 7w3d (originally thought I was 8w3d and my doctor has been discussing the genetic testing they do at 10w for chromosome abnormalities and other such things. She said they extract the fetal cells from my blood and grow them to look at the chromosomes and consequently while doing that they can tell the gender because of the X and Y chromosomes. She also said if they can’t successfully grow the fetal cells they will redraw blood. To me, that all sounds pretty fool proof especially if they’ll be looking that closely at everything. So I’m just wondering if anybody knows the accuracy of the gender result because it will obviously be earlier than the standard ultrasound and I would love to throw a small gender reveal party for family when I get my result (around 13 weeks) but don’t want to if there’s a decent chance it’s inaccurate. Anybody have experience with this or know the science and reliability behind it?