How do Kegels help in labour?

Kr

I'm 26 weeks pregnant and starting last week I started feeling like my vagina is ummm... going to fall out! I think the baby is lying low and puts a lot of pressure but I don't think this is sustainable in the long run.

This app is constantly asking if I've done my kegels. Well maybe now I should start, right?

How are these exercises supposed to help?

Thank you