This section details your appointment schedule, along with the various tests you will be offered during your pregnancy.

 

+ Antenatal care

Your first visit with me will generally be at 10 weeks gestation followed by visits at 16, 21, 24, 28, 31, 34 and 36 weeks, and then weekly until delivery. You will also meet with Midwives Tristen or Jac at 13 and 26 weeks to prepare for childbirth and the postnatal period. You will then meet Midwives Amber or Alex at 37 weeks for a 1:1 newborn feeding education class. Your partner/support person is very welcome to attend all your antenatal visits and will be most welcome at the birth of your baby. Please note that in some cases, you may need to see me more often, especially if your pregnancy is high risk.

It is important to discuss any questions with me and I will always make every attempt to answer them. It is often helpful to list these questions because you may forget to ask them during your antenatal visits.

Every attempt will be made to see you at your appointed time, although occasionally there may be a delay. This usually occurs because another patient needs to be delivered during a consulting session. If this happens you will be offered another appointment, although you are welcome to wait until I return. Children are welcome, but we have found that they may be intolerant if there are long delays. It is always wise not to commit yourself immediately following your appointment.

+ Postnatal care

At approximately 7 days after birth you will be visited at home by Midwife Amber or Alex at a time that is convenient to you - the Midwives will discuss with you how best to get in touch at your 37 week feeding class. This visit is designed for an overall health check of baby (assessments for jaundice, feeding and settling advice and any other concerns) as well as a check for your physical and mental health.

Your postnatal visit will be 6 weeks after delivery and you should ring my rooms to arrange this soon after you leave hospital. Your partner is very welcome to attend this appointment.

+ Genetic testing

One of the complex choices to make in early pregnancy is that of prenatal testing. In recent years, several new tests have become available primarily aimed at testing for Down syndrome. These tests are offered in addition to the usual blood and urine tests in early pregnancy, and are also additional to the detailed ultrasound examination at around 20 weeks. These tests are looking for various genetic conditions in your baby.

These tests are optional but need to be considered carefully. You should not feel pressured to undertake any of these tests if you do not wish to do so. It is important to recognise that the choice of testing, and what you do with the results, is yours. I will give you advice on the different types of tests and options available but the ultimate decisions must rest with you.

There are two main groups of screening tests available to you:

  • Genetic tests performed before or very early in pregnancy
  • Prenatal tests performed at various stages throughout pregnancy

1. Genetic tests performed before or very early in pregnancy

Genetic carrier screening is now offered to all couples before or very early in pregnancy to see if they are carriers of particular genetic conditions that can affect their future children. Whilst some ethnic groups are more likely to carry some genetic changes, carrier screening is now offered regardless of ancestry. This testing usually only needs to be done once in a couple’s reproductive years as results will be applicable to all future pregnancies. Most babies born with these genetic conditions have no known family history of the condition. That is, the parents did not know that they were carriers of the same condition.

Genetic carrier screening can be done for just a few conditions (‘Prepair’), or part of an expanded panel of over 100 conditions (‘Counsyl’ or ‘Virtus’). If you are not a carrier of these conditions, you are at very low risk of having a child with any of these conditions. It is important to know that the current carrier tests detect the majority of carriers, but they cannot detect every single gene change that can cause these conditions.

The three most common conditions which are tested are Cystic Fibrosis (CF), Fragile X Syndrome (FRAX) and Spinal Muscular Atrophy (SMA). The combined test, called “Prepair” costs approximately $385 and you will be billed directly by the laboratory, Victorian Clinical Genetic Service (VCGS). These types of genetic tests are unfortunately not eligible for rebate under the current Medicare scheme. If your test is positive for any one of these conditions then your partner can be tested for the single relevant condition. If you or your partner are found to be carriers of CF, SMA or FRAX, I will organise immediate genetic counselling so that you can be advised about your risks and options for further testing. Results take approximately 10 working days and I will contact you directly with the results. Please note that testing positive to carrier status does not mean you have or will develop the disorder yourself.

Cystic fibrosis

Cystic fibrosis (CF) is an inherited condition that affects approximately 1 in 2,500 babies. One in 25 Caucasians are carriers of CF. If both parents are carriers, each of their children has a 25% chance of inheriting the disorder. CF causes thick mucus in the lungs and gut, resulting in recurrent lung infections that cause progressive damage and difficulty with digestion of food. Infants and children with CF require daily chest physiotherapy, frequent courses of antibiotics, and the need to take medicine to aid digestion. Until recently many children with CF died in early childhood but now the average life expectancy is about 40 years of age. There is no cure for cystic fibrosis but better treatments are under research and development.

The gene that causes CF is called CFTR. The test from VCGS will detect about 90% of people who are carriers of a cystic fibrosis gene change / mutation. A couple is only at risk of having a child with CF if both parents are carriers of the condition. If the tests show that you are a carrier for CF, your partner will be offered testing to clarify the risks for your child / children.

Fragile X syndrome

Fragile X syndrome (FXS) is the most common cause of inherited intellectual disability affecting around 1 in 4,000 babies. Approximately 1 in 100-150 people are carriers of FXS. People with FXS can have developmental delay, learning difficulties, anxiety, autism and epilepsy. The features of FXS vary from mild to severe with males more likely to be severely affected than females. There is no cure for FXS although some educational, behavioural and medical interventions can improve outcomes. Some females who are carriers of FXS may have early menopause.

FXS is caused by an increase in the length of a particular gene known as the FMR1 gene, located on the X chromosome. The VCGS test will detect about 97% of people who are carriers of FXS. Only female carriers of FXS are at increased chance of having a child with FXS (males can be carriers, but they cannot produce a child with FXS). Therefore, your partner does not need to be tested. If you are a carrier of FXS, your baby can inherit the FXS gene change. Your baby may then either be a carrier of FXS or may actually have FXS. FXS is a very complex genetic disorder and genetic counselling is highly recommended if you are found to be a carrier.

Spinal muscular atrophy

Spinal muscular atrophy (SMA) affects approximately 1 in 6,000 babies. One in 40 individuals are carriers for SMA. SMA is a condition that affects nerves in the spinal cord and causes muscles to get weaker. There are four types of SMA. SMA Type I is the most severe. Babies with SMA Type I have weak muscles from birth and usually do not live past two years of age. SMA Types II and III progress more slowly than Type I. Most children with SMA Types II or III are unable to stand or walk without help. Children with Types II and III SMA can live into early adulthood, depending on the severity of the condition. People with SMA Type IV do not develop symptoms until adulthood. There is no cure for SMA, however there are treatments and interventions available aimed at managing symptoms and improving quality of life.

There are two genes which cause SMA, called the SMN1 and SMN2 genes. The VCGS test will detect about 97% of people who are carriers of SMA. A couple is only at risk of having a child with SMA if both parents are carriers of the condition. If the tests show that you are a carrier for SMA, your partner will be offered testing to clarify the risks for your child / children.

2. Options for prenatal screening

There is now a bewildering array of tests available during pregnancy and thinking about these types of tests can be quite confronting as they can detect some serious medical conditions in a baby. It is important to realise that by having any of these tests there is no assumption that you will terminate a pregnancy should it be affected. Please be assured that if there is a serious condition detected, I will support informed decision making and perform a termination of pregnancy, if requested.

No testing

Some people choose to do no additional prenatal testing at all. Perhaps the risk of these conditions are considered to be low, or because termination of pregnancy would not be considered under any circumstances. This is a completely appropriate decision that is entirely yours to make. I would still recommend routine pregnancy blood tests and a 20 week ultrasound, which we can discuss at your appointments.

Ultrasound only – nuchal translucency (NT) scan

All babies have a small fluid-filled space under the skin at the back of the neck (the NT). If this space is enlarged (that is, there is an increased NT), there is a higher chance of having a baby with Down syndrome or other genetic or structural abnormalities such as heart problems. This is assessed with an ultrasound scan between 11 and 14 weeks. If the scan shows an increased nuchal translucency, then further investigations will be recommended, usually in the form of invasive testing, such as a CVS or amniocentesis. An ultrasound at this stage has the added benefit of early detection of many unrelated physical abnormalities. In most instances this ultrasound is done as an abdominal scan but if the area on the back of the neck cannot clearly be seen then a vaginal ultrasound will be recommended. Of course, you have the option to decline this type of examination if you prefer. Most babies with an increased nuchal translucency are completely normal.

Non-invasive prenatal testing (NIPT)

Several non-invasive prenatal genetic tests are available, which all test a maternal blood sample from 10 weeks of pregnancy. These tests analyse cell-free fetal DNA found in the mother’s blood to detect Trisomy 21 (Down syndrome), Trisomy 18 (Edwards syndrome), Trisomy 13 (Patau syndrome) and Turner syndrome. The test is highly sensitive. NIPT is known by several different names, the two most common being Harmony and Percept. I recommend all my patients consider NIPT as it is the best non-invasive screening test for Down syndrome available. The cost is about $450, and there is no Medicare rebate or private health coverage. Results are available within 3-5 days from the time the sample is received by the laboratory. If you have a positive result, you will need a diagnostic test to determine if the baby is truly affected.

First trimester combined screening (FTCS)

The FTCS involves combining the results of the nuchal translucency scan with the results of a blood test performed between 11 and 14 weeks. The FTCS is directed at detecting Down syndrome, Edwards syndrome and Patau syndrome. An approximate out of pocket cost for the blood test after Medicare is $70, but this does not include the cost of the ultrasound. Results of this testing are reported as low risk or increased risk. Increased risk results (>1:300) do not mean there is something wrong with the baby, just that additional testing can be performed to clarify the result. Most babies with an increased risk on the combined first trimester test are completely normal. Results will be available within two weeks from when the blood test was taken.

Maternal serum screening test (MSST)

The MSST is a blood test performed between 14-20 weeks (ideally between 15-17 weeks) to determine if you may be at risk of having a baby with Down syndrome, Edward syndrome or a neural tube defect. This test does not diagnose these conditions but identifies high-risk women (>1:250) who could be offered further testing. The results are usually available within one week and will be reported as low risk or high risk for each of these conditions. It is important to remember that most women with a high risk will go on to have a normal baby. While this test is Medicare funded with an out of pocket cost of $70, it is not the most accurate screening test for Down syndrome available and so I do not recommend it. Results will be available within one week from when the blood test was taken.

3. Diagnostic testing

Diagnostic tests are performed in women who have high-risk prenatal screening tests, or are particularly high risk for genetic problems for other reasons. They are confirmatory for the presence of genetic abnormalities.

Chorionic villus sampling (CVS)

CVS involves passing a needle into the placenta between 11 and 13 weeks gestation. A small amount of placental tissue is taken and a chromosome analysis is then performed by the pathology laboratory. Full results take approximately 8-14 working days to become available. FISH testing is a more rapid test on the sampled tissue that detects a smaller number of conditions, including trisomies 21, 18 and 13, and the results of this are available within 24-48 hours at an additional cost. Further details of the actual procedure will be given to you if this is the option you choose. The sensitivity of CVS for detection of Down syndrome is virtually 100%. The only exception would be a technical problem growing the placental cells in the laboratory, and in these unlikely circumstances an amniocentesis may be required later in pregnancy. The risk of miscarriage from the procedure itself is 0.2-1% (you must remember that there is a risk of spontaneous miscarriage at this gestation of approximately 2%).

Amniocentesis

Amniocentesis involves taking a small sample of amniotic fluid from around the developing baby after 15 weeks gestation. Only a small amount of fluid is taken but this is enough for a full chromosome analysis to be performed. Full results take approximately 8-14 working days to become available. FISH testing is a more rapid test on the sampled tissue that detects a smaller number of conditions, including trisomies 21, 18 and 13, and the results of this are available within 24-48 hours at an additional cost. The sensitivity of amniocentesis for detection of Down syndrome is virtually 100%. As with CVS, there may be a technical failure to grow the cells in the laboratory but this is extremely uncommon. The risk of miscarriage from the procedure itself is approximately 0.1-0.5%. The risk of spontaneous miscarriage at this gestation is 0.5%.

Test

Weeks pregnant

Detection of Down Syndrome

False positive rate

PPV

NT test

11-14

70%

5%

-

NIPT

>10

99.9%

<0.1%

45-90%

Combined first trimester test

11-14

85-90%

5%

7-10%

MSST

14-20

75%

5%

2-3%

CVS

11-13

100%

0%

100%

Amniocentesis

>15

100%

0%

100%

+ Ultrasound in pregnancy

I recommend that you have the following ultrasound scans during your pregnancy:

  • Dating scan – this is ideally performed between 6-9 weeks gestation to determine your due date
  • Nuchal translucency scan – this is performed between 11-14 weeks gestation. It forms part of the FTCS and has the added benefit of early detection of many unrelated physical abnormalities. I therefore recommend it to all pregnant women, even those who have NIPT as their prenatal screening test
  • Morphology scan – this is performed between 18-22 weeks gestation and assesses the anatomy of your baby, as well as the location of your placenta and the length of your cervix

Additional scans for growth and well-being may be organised throughout your pregnancy, and I will discuss these with you if they are required.

Importantly, medical ultrasound is completely safe and routine scanning during pregnancy is not contraindicated. There are no known adverse biological effects associated with obstetric ultrasound.

+ Gestational diabetes testing

Gestational diabetes mellitus (GDM) is a common type of diabetes related to pregnancy, affecting up to 18% of pregnant women. It occurs due to hormonal changes causing insulin resistance – the body is then unable to produce enough extra insulin to meet its increased needs in pregnancy.

I recommend that all my patients are tested with an oral glucose tolerance test (GTT) at 26-28 weeks gestation. This is a fasting blood test – please ensure you have had nothing to eat or drink (other than plain water) overnight for 8-12 hours prior to having your test. Water is allowed anytime overnight, and I suggest that you maintain adequate water consumption to ensure good hydration. After the initial blood test, you will be given a glucose drink, and further blood tests will be performed at 1 hour and then 2 hours after the drink to check your blood sugar level. You will therefore need to stay at the collection centre for 2 hours and 15 minutes from the time you are first attended to.

If you are at a particularly high risk of having diabetes, I will also test you earlier in your pregnancy (usually between 10 and 16 weeks) with a GTT. If the result is normal, you will need to repeat the GTT at 26-28 weeks.

+ Group B Streptococcus (GBS) screening

I recommend that all of my patients planning on having a vaginal birth have a GBS swab test performed at 35-36 weeks gestation. GBS is a common bacterium found in the vagina and bowel of about 15-20% of women. It causes no harm to you. However, if GBS is passed from you to your baby around the time of the birth, there is a small chance your baby will develop an infection and become seriously ill. Your baby is more likely to become infected if:

  • It is born prematurely
  • You have previously had a baby who developed GBS infection
  • You have a temperature of 38 degrees or higher during labour
  • Your waters break more than 18 hours before your baby is born

To reduce the risk:

  • If you are GBS positive you will be given antibiotics in labour. The antibiotic of choice is penicillin. Please make sure to tell me if you are allergic to penicillin, so that an alternative antibiotic such as clindamycin can be prescribed instead
  • If you have a urinary tract infection caused by GBS it should be treated, and you should be given antibiotics in labour
  • If you have previously had a baby with GBS infection you will be given antibiotics in labour
  • If you are GBS positive at term (after 37 weeks), and your waters break before you go into labour, you will be advised to have your labour induced

It is safe to breastfeed if you are GBS positive.

+ Post-dates (overdue) pregnancy

If you have not given birth by 41 weeks gestation, I will arrange for you to have monitoring to check the well-being of your baby. I will also offer you an induction of labour at or shortly after 41 weeks gestation to reduce the risk of complications. Should you choose not to be induced, I will recommend regular fetal monitoring until your baby is born.