Dr Chang T.C.

Obstetrics Obstetric Ultrasound

Dr. Chang is the Head and Clinical Director, Fetal Assessment Centre, Singapore Women's Medical Group, a position he has held since 2020. Prior to that, he was the Head and Consultant in Maternal Fetal Medicine, Fetal Assesssment Unit, Thomson Medical Centre for the past 22 years (1998 – 2020). He performs Level III obstetric ultrasound scans for high-risk pregnancies, amniocentesis and chorionic villus sampling procedures. He is also accredited by the Fetal Medicine Foundation (London) to perform first trimester Nuchal Translucency ultrasound (accredited since 2000).

Dr. Chang has taught obstetric ultrasound in various Obstetric Ultrasound courses and has given numerous lectures at International Scientific Meetings on Obstetric Ultrasound and invasive procedures (amniocentesis / CVS) in numerous countries (UK, New Zealand, Canada, USA, Singapore, Malaysia, Hong Kong, Taiwan). Dr .Chang is a member of the British Society of Maternal Fetal Medicine, British Society for Genetic Medicine, Fetal Genomics Group, Australian Society of Ultrasound in Medicine and International Society of Ultrasound in Obstetrics and Gynaecology.

His special areas of interest are:

Non-invasive Prenatal Testing
Panorama Test (after 9 weeks of pregnancy) – what to do with abnormal results, no-call (non-informative) results, screen positive results for Trisomy 21, Trisomy 18, Trisomy 13, Monosomy X, 22q11 micro-deletion
First Trimester NT Ultrasound Scan
First trimester (11 – 14 weeks) NT ultrasound scan to screen for fetal structural abnormalities and fetal chromosome abnormalities
First Trimester Screening
First trimester screening for Pre-eclampsia to identify high-risk patients who may benefit from low-dose aspirin therapy
Genetic Ultrasound Scan
Genetic ultrasound scans to assess risk of fetal chromosome abnormalities and genetic syndromes
Fetal Anomaly Scan
Level III Fetal Anomaly scan to screen for fetal structural anomalies (eg. complex fetal heart abnormalities), counseling and discussion about prognosis
Prenatal Invasive Procedures
Prenatal invasive procedures (amniocentesis, CVS and fetal blood sampling)
Assessment of pregnancy
Ultrasound assessment of high-risk and complicated pregnancies (twins, pregnancies with pre-eclampsia, fetal growth restriction)
4D ultrasound
4D ultrasound

Ultrasound Assessments

What are the different important assessments?

First Trimester Combined Screening
(also known as OSCAR)
Nuchal Translucency (NT) Ultraosund scan together with serum biochemistry (PAPP-A and beta-hCG). This scan and blood test is performed between 11 weeks and 14 days of pregnancy. It can detect up to 90% of all pregnancies affected by Downs syndrome. As an alternative, Dr Chang also recommended the NT scan combined with the Panorama test (NIPT) at 11-14 weeks. This can screen for up to 99% of all pregnancies affected by Down’s syndrome.
Fetal Anomaly Ultrasound Scan
This scan screens for major fetal malformations, including abnormalities of the brain, face, heart, lungs, intestinal system, kidneys, spine and limbs. It is performed between 18 and 21 weeks of pregnancy.
Growth and Doppler Ultrasound Scan
(Uterine, Umbilical, Middle Cerebral, Ductus Venosus) to help detect early signs of oxygen deprivation in the growth restricted fetus.
Invasive fetal medicine diagnostic procedures
diagnose fetal chromosome abnormalities (Downs syndrome, Edwards syndrome, Pataus Syndrome).