CHORIOAMNIOTIC SEPARATION AFTER 2ND-TRIMESTER GENETIC AMNIOCENTESIS -IMPORTANCE AND FREQUENCY

PURPOSE: To determine the frequency and importance of chorioamniotic s eparation (CAS) after second-trimester genetic amniocentesis. MATERIAL S AND METHODS: In part 1 of the study, ultrasonography (US) databases were reviewed for cases of CAS. In part 2, a study population of 388 w omen undergoing amniocentesis underwent directed US examination for as sessment of CAS 15 minutes and/or 2 weeks after amniocentesis. CAS, wh en present, was graded. A control population consisted of 363 women un dergoing amniocentesis in whom the membranes were not assessed. RESULT S: In part 1, a review of 23,883 records revealed seven cases of compl ete CAS, with three deaths, two preterm deliveries, and one emergency cesarean section delivery due to fetal distress. In two of these cases , there were extremity deformities at birth. In part 2, CAS was presen t in 98 (25%) of 388 women at some point. There was no association bet ween CAS and procedural variables. There was no substantial difference in morbidity between patients with and those without CAS, between pat ients with different grades of CAS, or between the study and control p opulations. CONCLUSION: Small degrees of CAS are frequently present af ter amniocentesis but are not detected because the membranes are not s pecifically evaluated. Complete CAS is less frequent.