When is the earliest that I can ask for a c-section?

What did your OB say. For my pts, if it is elective u can do it at 39 weeks gestation, 1 week before your due date, if it needs to be done before that then u need a specific medical reason and your OB is supposed to do an amniocentesis to make sure the lungs are mature, you need to discuss this with your OB before the last minute so everyone is on the same page.