CHROMOSOME ANALYSIS OF CHORIONIC VILLI

Lab Section Category	Cytogenetics – Prenatal View write-up
Specimen Required	Chorionic villi (10 - 30mg) by transabdominal or transcervical sampling in a sterile tube containing transport medium supplied by our Cytogenetics Laboratory.
Indications	- 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 - High risk non-invasive prenatal test (NIPT)
Method	In situ coverslip technique
Test Results	Normal or Abnormal. If Abnormal, the karyotypic abnormality is described in accordance to the International System for Human Cytogenomic Nomenclature (ISCN, 2024).
Turnaround Time	8 ~ 14 days
Day(s) Test Set up	Monday - Saturday (office hours)
Remarks	Indicate clearly the clinical indications, gestation age, LMP, EDD and weight of villus samples taken on the cytogenetics request form or CPOE. Do not despatch a specimen near a weekend or a public holiday to avoid unnecessary delays.

Change History Notes

21 Oct 2025 11:02 AM

Updated test results for ISCN, 2020 to ISCN, 2024
18 May 2022 10:30 AM

Updated Indications to include - High risk non-invasive prenatal test (NIPT)
Updated the test result for ISCN, 2016 to ISCN, 2020
06 Jul 2017 10:55 AM

Updated the test result for ISCN, 2013 to ISCN, 2016
08 Dec 2015 08:35 AM

Updated Turnaround Time: 8 ~ 14 days

Last Updated - 21 Oct 2025