Distressed mom to be

I don't really have an issue with Discovery or their services, but I do have a problem with the lack of knowledge or willingness to share information which is vital for their clients to know. I am pregnant and have not had a good experience thus far, I have just been hitting a brick wall. I am on the Keycare Plus plan since we as a family do not really use the medical aid, we have it in case of an extreme emergency. The problem is that now that I need to medical aid to work for me, we have been told by the network Gynae's that they can only see us up to 5 months and then we need to find someone else to help through the remainder of the pregnancy as well as birth. How is this possible and how is is justified? Have they taken this stance because of the rates Discovery pays or what has changed? I have yet to have my first gynae appointment as I am struggling to find one who can see me right through. This is a very personal and daunting experience, how can they expect us to jump from person to person. None of the consultants can tell me why this is how the gynaes work and neither can assist with finding a gynae that will take the journey with me. No one can tell me what happens after 5 month when these gynae's walk away. Do i have to find someone new and then have to foot the bill because it will not be a network Dr, all the while I am still paying my medical aid and then I have find money to pay for the birth. If I had this amount if disposable income, I would not be on the health plan that I am on. This is really distressing and I have not enjoyed one minute of my pregnancy as we are stressing as to how we are going to go about this. If someone can please just tell me what I am paying medical for and where are the Gynae's that are willing to see one through term.