Twin Reduction: Transvaginal Aspiration

Transvaginal aspiration of the allantoic fluid or yolk sac contents from a conceptus is one method of eliminating one conceptus in a twin pregnancy. This technique requires specialized equipment such as a transvaginal ultrasound unit and the technical skill to safely and efficiently perform the procedure. The procedure is generally performed from day 20 to day 45 of the pregnancy, but may be attempted until the uterus is no longer able to be retracted into the pelvic inlet, which may extend to beyond day 60. The chapter discusses step by step procedure for twin reduction and the equipment and supplies needed. It also discusses necessary conditions for twin reduction.