The results of cytogenetic
analyses revealed an abnormal ketoacidosis in 19
pregnancies (4.3%), nine of which were trisomy
21. The overall spontaneous loss rate was
0.89% (n = 4). Conclusion: It would be useful for
each center to investigate its own pregnancy
loss rate and thereby provide a firmer basis for
its policy for counseling women requesting
amniocentesis. If enough such investigations
were reported, a true benchmark fig