Who did you have with you while in labor? Mother in law?

So my initial plan for labor was to wait it out as long as possible at home so I would be more comfortable but I just found out I'm gbs positive so I'm going to have to go to the hospital asap so that there's ample time to receive antibiotics through an IV. 

I'm a very private person and plan on having my husband and mother present for the actual birth.  I'm a first-time mom so I'm wondering when I'm actually in labor (which I know could be a really long time)  who did you have there with you?

 I want to do this as natural as possible and I know I'll be in a lot of pain.  My mother in law told me yesterday that as soon as I get admitted to the hospital to call her so that she can be there.  I know I'm new at this but I don't think I'll want her there during that time that I'm in labor, especially that she'll have to wait there for what possibly could be long hours.  I'm not sure if she's just hoping that i will let her be there for the actual birth since she'll be waiting there anyways.  When is it that I should  tell her it's time to go to the hospital?