Most pregnancies are normal and a sequence of routine antenatal tests are performed on all pregnant women.
Early pregnancy ultrasound scans can be performed on a weekly basis until 10 weeks gestation in every pregnancy believed to be at risk of miscarriage. Ultrasound scans will also be performed if there is any concern about the pregnancy. (e.g. after falls, bleeding, and reduced fetal movements etc.).
Initial routine antenatal blood tests are performed at 10 weeks gestation.
This comprehensive list of tests would include all the routine antenatal tests. They would also include other tests such as viral serology to check on your immunity to diseases that could cross the placenta and cause fetal harm in pregnancy.
Screening for inherited disorders (Cystic Fibrosis, SMA Spinal Muscular Atrophy and Fragile X syndrome) are available and these tests would be discussed and offered as options for further testing at 10 weeks gestation, if indicated.
Chromosome anomalies testing are offered to all pregnant patients. Screening tests include:
The combined first trimester screening test
This is a blood test performed after 10 weeks and is combined with a 12 week ultrasound scan.
Non-invasive prenatal screen
This is called the N.I.P.S test and is a new test using the latest technology to identify chromosome anomalies. It has become the preferred test requested by most patients. It involves a blood test alone performed at 10-11 weeks (The Harmony or Percept Test).
For High Risk Patients we would offer patients the option of Diagnostic testing (Invasive Tests):
- Amniocentesis (performed at 16 weeks) Miscarriage rate 0.5%.
- Chorion Villus Sampling CVS (performed at 11 weeks) Miscarriage rate 1%
Fetal morphology ultrasound scans
High quality fetal anomaly scans are performed by specialist women’s ultrasonologists to improve detection rates of fetal structural anomalies. They are performed at 20 weeks gestation.
Any possible anomalies that might be found would then be followed on serial scanning.
In select situations such patients may be referred for even more specialised scanning (e.g. Heart, Brain scans etc.).
In select cases, of complex pregnancies I would engage specialists at The Royal Children’s Hospital and also involve tertiary obstetric units in Melbourne.
Fetal growth scans
Fetal growth scans are routinely performed at 34 weeks gestation.
If clinical assessment or ultrasound evidence suggests possible fetal growth restriction, serial scans would be performed to monitor fetal well-being through the remainder of the pregnancy. These scans are focused on testing umbilical and cerebral blood flow, fetal growth and amniotic fluid volume.
Selective blood tests
Subsequent selective blood tests are also routine in all pregnancies and are performed at 28 and 36 weeks gestation. They include testing for:
- Gestational Diabetes. (GTT at 28 weeks)
- Thyroid function tests and Thyroid antibody tests
- Vitamin and mineral deficiencies (28 and 36 weeks)
- Antibody screens in all Rh Negative women (28 and 34weeks)
Tests of fetal well-being
Ultrasound scans - Cardiotocography (CTG’s) are performed in all high-risk pregnancies and in women with reduced fetal movements.