| The only definitive test involves chorionic villus sampling and amniocentesis but that carries a risk of miscarriage. |
| In cases where Down syndrome is suspected, the disorder can be confirmed using amniocentesis or chorionic villus sampling. |
| First trimester villi samples were collected from leftover material obtained via chorionic villus sampling. |
| Using chorionic villus sampling techniques, examination will in many cases be possible as early as the 10th week in the near future. |
| Early amniocentesis offers a similar advantage, but the fetal loss rate associated with this technique is higher than that of chorionic villus sampling. |
| These options include amniocentesis, early amniocentesis, chorionic villus sampling, and ultrasound examination. |
