When did your dr tell you to go to the hospital for labor and delivery?

Just curious to see what other women were told about when to come in/when it would be recommended etc. I'm delivering with a midwife and they want me to be in active labor with my contractions 3 minutes apart. - that's as a first time mom they recommend sooner if it was my second child. Is that normal ? I was fine with it until my mother was getting concerned about me giving birth in the car or something. But she has a tendency to be a worrier so I'm taking it with a grain of salt for now