I arrived at the maternity ward, they checked me out, my cervix was al…

I arrived at the maternity ward, they checked me out, my cervix was almost 1 inch dilated. The ultrasound showed everything is fine. But these contractions were just practice. The blockage wouldn't budge. I ended up lying in the maternity ward just in case. I wanted to ask those who gave birth, how long did you wait for labor after the onset of premonitory signs?