KARYOTYPE AMNIOTIC FLUID
- Advanced maternal age (≥35 years at EDD) - Abnormal ultrasound findings - Positive maternal serum screening - Previous history of chromosome abnormality - Family history of Down syndrome - Parental anxiety
Amniotic fluid (15 – 25ml) from between the 15th and 16th week of gestation. Discard the first 2ml of the aspirate. Use a sterile 25 or 30ml syringe. Draw and transfer the specimen into two sterile screw-capped 15ml V-shaped tubes. Bloody specimens are undesirable. If growth is inadequate, you will be notified within 14 days of receipt.
Normal or Abnormal. If Abnormal, the karyotypic abnormality is described in accordance to the International System for Human Cytogenomic Nomenclature (ISCN, 2016).
8 ~ 14 days
Monday - Saturday (office hours)
Indicate clearly the clinical indications, gestation age, LMP, EDD and volume of fluid taken on the cytogenetics request form or CPOE. Do not despatch a specimen near a weekend or a public holiday to avoid unnecessary delays.