Effect of cervical traction with a tenaculum on the uterocervical angle.

The effect of cervical traction on the uterocervical angle was measured radiographically in 24 women undergoing diagnostic curettage. A radio-opaque guidewire was inserted through the cervical canal into the uterine cavity and a lateral pelvic X-ray taken before and after traction. The traction force was measured with a spring-balance attached to the tenaculum. Cervical traction in a caudal direction (force 2 N) reduced the median uterocervical angle, from 75 degrees to 10 degrees (P = 0.001). Moderate cervical traction straightens the uterus and the routine use of a tenaculum theoretically makes insertion of an intrauterine device safer and the passage of an embryo transfer catheter less traumatic.