if a woman mentions to you that she has pelvic pain, you need to ask her to contact her doctor so that she can find out the cause of the pain.
It happens from time to time that clients say that they are having pain and want to work out nonetheless. There are cases when we can work around: for example, a person with a broken toe can still do a lot of things, mainly upper body. But in the case of unexplained pain, particularly in a region required to provide stabilization for any exercise that you do, it is not safe to proceed.
If a client absolutely wants to work out regardless, let her be on her own and not under your direction. But tell her that you advise against it.
Hope this helps.