Comparison of results between use of precocious and conventional amniocentesis

Verify the incidence of failure of culture and loss of fetus resulting from precious amniocentesis (prior to 15 weeks) and conventional amniocentesis (after 15 weeks) and to compare the results obtained with the two procedures. Between 1993 and 1997 precocious amniocentesis was realized in 975 cases and conventional amniocentesis in 918 cases. For this purpose 22 g needle was used with due care to avoid transfixation of placenta, removing approximately 20 ml of amniotic liquid. In the group of precocious amniocentesis failure of culture was observed in 1.553% (n = 15), there was 0.61% (n = 6) of fetal loss, and 2.05% (n = 20) of altered cariotypes. In the conventional amniocentesis group the following values were registered. 1.415 (n = 13) of failure of culture, 0.54% (n = 5) of loss of fetus and 1.74% (n = 16) of altered varitypes. The results of the present study permit to conclude that no increase in the incidence of failure of culture and loss of fetus could be observed when precocious amniocentesis was used considering conventional amniocentesis as reference.