Mityvac® Bell Cups have a large diameter mouth to distribute tractive force across the fetal scalp. These cups can be used for low occiput anterior and outlet presentations.
The patented Mityvac® MitySoft® Bell Vacuum Cup is the softest bell-shaped cup on the market. It has an enhanced flared edge mouth that features a soft "siliconess" lip that helps to minimize infant scalp trauma and damage to maternal tissue.
Soft Bell cups result in less trauma for occiput anterior presentations:
1Johanson R et al. Cochrane Database Syst Rev. 2000; CD000446. A Cochrane analysis of data from 9 trials including 1375 women, concluded that soft cups were associated with less scalp injury than rigid cups (odds ratio 0.45; 95% confidence interval 0.15-0.60).
2Greenburg J. Procedure for vacuum assisted operative vaginal delivery. In Rose BD, ed. UpToDate. Waltham, MA 2005. Rigid cups tended to be more suitable for occiput posterior, occiput transverse, and difficult occiput anterior position deliveries, while soft cups appeared to be more appropriate for uncomplicated occiput anterior deliveries.The rigid M-style® cup is recommended for deliveries likely to require greater traction forces.
3Hayman, R et al. Clinical evaluation of a "hand pump" vacuum delivery device. Obstet Gynecol. 2002; 100:1190-1195. Scalp laceration rates: Kiwi OmniCup - 14.1%, metal cups - 11.1%, standard vacuum device - 4.5%.