TECHNICAL ASPECTS OF TRANSCERVICAL CHORIONIC VILLUS SAMPLING

Following the 1990 FDA approval of the Trophocan((R)) catheter for use in transcervical chorionic villus sampling (CVS), an increasing numbe r of US physicians have begun offering the procedure. To obtain privil eges to perform CVS, some states such as California have enacted legis lation requiring the performance of a certain number of CVS procedures in pregnancies in which the patient has already chosen first-trimeste r abortion. This practice is not universally feasible for legal, logis tic, or financial reasons. We describe our approach to training in a b usy reproductive genetics service. The physician initially trains by p erforming amniocentesis to optimize skills in ultrasound-directed need le guidance and placement. During this initial period, he or she also assists in performing transabdominal CVS procedures. The initial trans cervical CVS cases should be performed in those situations requiring m inimal catheter manipulation, or in those individuals undergoing CVS i n the setting of spontaneous abortion. Cases of increasing difficulty should only be performed as skill and familiarity increase, For a phys ician already skilled and experienced in ultrasound-guided invasive pr ocedures, sequential periods of observation at a busy center allows hi m or her to become familiar with the common pitfalls in performing tra nscervical CVS, and thus avoid them. Using this approach, we have perf ormed over 5,000 CVS procedures and trained 6 reproductive genetics fe llows in transcervical CVS.