Hi there. The truth is no one can count 100% on the epidural. Sometimes it only works on half the body, etc. With your medical history, you may not be eligible for it, or it may be riskier than normal. For that reason, you may want to prepare yourself to get along without it, which is totally do-able despite what everyone will tell you. (I had 2 natural childbirths and never considered pain relief once. The contractions were manageable as long as I was allowed freedom of movement, and it only got hard at the end, so an epidural would have been a waste).
A few things you can do to minimize feeling like you need pain relief are:
1) Insist on freedom of movement in the hospital and have someone (like a pushy friend or relative or an assertive doula) to make sure your wishes are respected. That means no lying in bed for hours with continuous electronic fetal monitoring and being a "bad" patient. But, honestly, being forced to have a natural labor sitting or lying in bed is just torture. It's movement and position changs that help you find the best way to cope.
2) Say no to Pitocin. Pitocin makes for contrax that are more intense and harder to handle, for both you and the baby. Despite the fact that it's used in 80% or more of labors in some hospitals, it has not been approved by the FDA for use and many professionals believe it is grossly overused. If you aren't dilating fast enough for the hospital, go into the bathroom bathtub or shower and close the door for awhile. Left alone and feeling safe, you'll likely dilate much faster.
3) Say no to induction. And induction is a sure-fire way to have a long, drawn-out labor that has a huge likelihood of ending in a C-section. Besides, since they typically use Pitocin to induce, you'll be dealing with extra-hard contractions. Want a relatively easy short, easy labor that you can manage without pain meds? The best thing to do is to wait until you're body is ready and let it happen naturally. Many times, when you do this, you can start labor already at 3 cms or so. Take it from me, it's totally the way to go, and I was 7 days "late" with both of mine. First labor: 9.5 hrs, second not even 3.5.
4) Don't go to the hospital too early. Unless you have a specific medical reason for it, it's better to get early labor done at home, and show up at the hospital closer to the end than the beginning. It keeps you off their clock and minimizes your stress level, helping you to have a more normal labor pattern.
5) Spend these last couple of weeks researching natural childbirth methods, good positions for minimizing pain, and hiring a good doula. Not only can it help you limit the stress of whether or not you'll want an epidural, it will give you confidence in your ability to birth your baby without it and make for a more positive and empowering birth experience overall.
You can do it. Honestly, in my opinion, when you have freedom to move and your labor does last 24 hours, it's not nearly as bad as everyone makes it out to be. Kind of like the hardest workout you ever did, but with a break every 2 mins. :)
Good luck!