Just a bit of general info on these Paul: these were worn by the female Feldscher or to give them their correct name, the 'Gesundheitsdienstmädel (GD-Mädel). The 'UD' stands for 'Unfalldienst'.
There was a further version of this patch for lower leaders with a red cord running around the outer edge. Both versions and also the HJ-Feldscher dark blue patch were discontinued on the 2nd of Sept 1938 and were replaced by the oval white patch with life rune in red.
The following configurations of the new patch existed and they denoted the appointment of the wearer:
Feldscher and GD-Mädel - oval white patch with life rune in red
Gefolgschaftsfeldscher/GD-Mädel der Gruppe - as for Feldscher but with green/white cord
Bannfeldscher/GD-Mädel des Untergaues - as for Feldscher but with red cord
Gebietsfeldscher/GD-Mädel des Obergaues - as for Feldscher but with black cord.
More stuff to look for
Well, certainly those last two and the UD patch with the cord. I haven't personally seen any of those in collections yet.