5 weeks ago (at 18 weeks) I was diagnosed with preterm premature rupture of membranes (PPROM).

4 weeks ago (19 weeks) I was referred to the Mayo Clinic where I was diagnosed with renal agenesis (no kidneys for baby).
Yesterday (23 weeks) our doctors at the Mayo Clinic decided that at this point they cannot determine definitively which diagnosis is the correct one.

As a result, they have decided that in order to give Siena the best possible outcome they will assume that we have PPROM until proven otherwise. This means that until an MRI or other test confirms she does/doesn’t have kidneys we will be cared for in the hospital close by to the NICU people.  As of now, I still have an MRI scheduled in two weeks which is the longest it could take to make the yes/no determination.   Several other tests could prove presence (making PPROM the final diagnosis), but nothing else will be relied on for absence. 
If the final diagnosis is PPROM I will stay in the hospital until delivery. This would happen no later than 34 weeks.
If the final diagnosis is no kidneys, I will be allowed to go home and wait for baby to set her own arrival.  Since renal agenesis is 100% fatal, there would be no inherent advantage to staying in the hospital for monitoring and the NICU.  
On one hand we have been given a huge ray of hope.   There is a possibility that Siena could survive if the final diagnosis is PPROM. On the other hand, even with that diagnosis we are a long way from out of the woods.  With every day I stay pregnant, I simultaneously decrease the risk of complications due to prematurity while increasing the risk of complications due to PPROM and an extended period of no fluid for baby.   Prematurity is inherently more risky, but regardless of prematurity Siena may need mechanical assistance with breathing for awhile which is part of the 34 weeks deadline.  Even at 34 weeks it is unlikely she would be merely a feeder/grower.  Our doctor here told us that while not all babies with prolonged PPROM survive, certainly some of them do.
So here I sit (lay) waiting for a final diagnosis that will come sometime in the next two weeks, we just don’t know when.   We are still working out lots of details on a daily basis to keep Tim working, kids happy and busy, and every once in a while doing a load of laundry.  We continue to cherish your prayers and encouraging words.  I will probably update on facebook more than the blog because the Internet connection here is awful and I don’t like typing long things on my iPad anyways.   On the flip side, I will probably bore you all with mundane details of life here on the antepardum floor!