Table 2 Principal macroscopic and microscopic findings regarding placentas complicated by aneuploidy
|  | Trisomy 21 (n = 31) | Trisomy 18 (n = 21) | Trisomy 13 (n = 3) |
|---|---|---|---|
Macroscopy | Â | Â | Â |
Hypotrophy | 16 | 12 | 0 |
Immaturity | 24 | 14 | 0 |
Sponginess | 20 | 10 | 0 |
Hydropsy | 24 | 20 | 0 |
Single umbilical artery | 0 | 4 | 0 |
Histology | Â | Â | Â |
Hydropic villi | 28 | 19 | 2 |
Immature villi | 20 | 6 | 0 |
Post-mature villi | 12 | 6 | 0 |
Calcifications | 4 | 4 | 2 |
Fibrin deposits | 12 | 4 | 0 |
Trophoblastic cysts | 0 | 4 | 0 |
Bullous dystrophy | 8 | 0 | 0 |