Midtrimester amniocentesis and culture of aminiotic fluid cells

On the basis of the large, well-controlled, prospective study from the NICHD, it can be stated that midtrimester ammniocentesis is safe if properly performed. The details of performance, with emphasis on possible pitfalls, are presented in an effort to encourage more practicing obstetricians to begin performing the procedure in cooperation with their area genetics laboratories (11). Emphasis is also placed on performing this procedure in a manner most likely to produce success. This success is measured not only in obtaining the fluid, but more importantly in gaining useful information from the analysis of the fluid. Although the aspects of diagnosing and preventing genetic disease have been emphasized, perhaps the greatest value of midtrimester amniocentesis is the reassurance afforded the more than 95% of couples when the fluid analysis is normal (19). The consumer demand for amniocentesis is rapidly increasing. Although the medicolegal implications of the techniques are not fully understood at present, it is clear that failure on the part of a clinician to offer indicated diagnostic amniocentesis may make the clinician vulnerable to litigation if the pregnancy outcome is abnormal. The demand for amniocentesis and laboratory analysis of the fluid will soon overtax existing facilities. Until such time as new and expanded facilities are available, discretion must be used in offering the procedures. Governmental action may soon be forthcoming to provide facilities designed to make midtrimester diagnostic amniocentesis available to all for whom it is indicated.