| Discomfort after installation of the pessary (1-2 days) | 4 women (1,9%) |
| Interval from removal of the pessary to delivery (days) | 10.5 (8-12) |
| Term of delivery (average, weeks) | 36.7 (34-40.2) |
| Delivery after the 34th week of gestation | 199 women (95.6%) |
| Delivery before the 34th week of gestation | 9 women (4.3%) |
| Duration of pregnancy prolongation (days) | 47 (18.1-62.1) |
| Cervical length <2.5cm | 48 women (23,07%) |
| Cervical length >2.5cm | 160 women (76,9%) |
| Dilatation of internal cervical os (>0.8mm) | 112 (53.8%) |