Invasive tests CVS and amniocentesis

These tests may be appropriate if there is a high risk for chromosome abnormality (Down syndrome etc). The CVS involves obtaining a tiny sample of placental tissue while an amniocentesis involves obtaining a small sample of the amniotic fluid. Both tests are done by passing a fine needle through the mother’s abdomen with continuous ultrasound scanning.

The initial results from either test, for Down syndrome and the other major chromosome abnormalities are usually available in 2-3 working days.

CVS is performed after 11 weeks and carries a 1 – 2% risk of miscarriage while amniocentesis is performed after 16 weeks and has a 0.5 – 1% risk of causing a miscarriage.

To book a scan appointment, please either telephone the Spire Alexandra Hospital (01634 662863) or the Kings Hill Medical Centre (01732 844244) or complete the online pregnancy scan booking form.