A miniature extraluminal force transducer for recording in vivo oviductal motility

A miniature extraluminal force transducer has been developed and used to record acute and chronic motility of the reproductive tract in the rabbit. This device, which contains two matched piezoresistive silicon sensors bonded to a titanium beam strip, is durable, physically stable, and highly sensitive to bending force (gage factor, 140). Acute recordings made in 20 rabbits revealed continuous, rhythmic contractile activity in both the oviduct and uterus. Chronic recordings made in three unanesthetized rabbits revealed periodic bursts of intense activity interspersed with periods of relative quiescence. Chronic implantation of these devices was accomplished with no evidence of infection, adhesions, or other abnormalities, and without disruption of fertility.