Are you experiencing Symphysis Pubic Dysfunction?
Here is some info to help you prepare for birth.
Rather than rewrite good information, I recommend this link on Pubic Pain
The article covers everything from what it is, what you can do during pregnancy and in regards to birth, this article goes into detail with the following:
"Planning for Birth
Certain common obstetric interventions tend to make Symphysis Pubic Dysfunction pain worse, and may even lead to ligament damage or severe separation of the joint, causing true Diastasis Symphysis Pubis. Therefore, it is vitally important that your doctor or midwife understand and believe in the existence of SPD and realize its implications for birth. The following ideas (taken from a number of sources) are supposed to help maximize your comfort and help the normal birth process, while also minimizing the risk for pubic symphysis-related trauma.
SPD is not to be taken lightly, and anyone who has experienced it knows how it can effect your enjoyment of your pregnancy and how it can inhibit your birth. I have been told by a woman who experienced SPD that the contractions were nothing, it was the feeling that her pelvis might explode that was unbearable.
Understanding SPD before labour starts, and preparing your birth plan accordingly, will help you reduce the effects of SPD during birth. Your birth map is written by you when you are rational and calm, this way when you are occupied with labour (and vulnerable and probably irrational) this becomes the go to document. It helps you (and your suppportors) to focus and remember your techniques, it provides your carers with clear instructions for your wishes. Your birth map contains your informed decisions for various scenarios.