Early amniocentesis at 10-12 weeks' gestation.

In this study we report the results of 181 ultrasound-guided genetic amniocenteses performed at 10-12 weeks of gestation and describe the indication, technical problems, amniotic fluid volume, culture success and timing, abortion and fetal loss rate, and perinatal results. Amniotic fluid was obtained in 98.4 per cent of the cases; at the first attempt, in 167 out of 181. The culture success rate was 94.5 per cent, and the fetal loss rate within 2 weeks was 0.5 per cent (one case with a sonographic abnormality). The total fetal loss rate during pregnancy was 1.6 per cent. A comparison of our data and those of other published series shows no significant differences, either with respect to this period of gestation (10-12 weeks) or with respect to the traditionally called early amniocentesis' (12-14 weeks) or conventional amniocentesis (15 weeks or more). The mean culture time was just a few days longer in some of the series, and in some cases, there was also a lower success rate after culture, particularly when amniocentesis was carried out at 10 weeks or less. We conclude that amniocentesis performed at 10-12 weeks is feasible, safe, and easy to perform, and provides a real benefit to the pregnant woman.