No gender confirmation at 5 months

Coco
I went to the doctor at my 5 month mark and they did an ultra sound. The baby moved a lot and they were only able to catch a tiny glimpse of the Genitals. She said her guess it's a girl but it's not for certain. She also said ultrasound is never for certain only blood work test. Has anyone done the blood work because they couldn't tell from ultrasound?