AFP testing

Kandi • Mom to 3 beautiful girls. Expecting august 2020

I went to my 16wk appt yesterday and the nurse said it was optional but that it was time for an AFP test that test for spina bifida and stuff anyone else had this done I opted in to have it done. it's done through bloodwork. I've never had this done with either of my previous pregnancies I mean one was 11 yrs ago so a lot has changed but my most recent was only 15mths ago. at my 12 wk appt they drew tons of blood and it was also for down syndrome and stuff. just wandering If anyone else has had this done or heard of it