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.
Your first visit will generally be at 10 weeks gestation followed by 16, 20, 24, 28, 31, 34, 36, 38 weeks then weekly till delivery. 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 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.
At your second visit you will receive your Pregnancy Summary. This contains important medical information, including your blood group, and you will be given an updated version at each visit. You should bring this summary to hospital when you are admitted.
At around 24 weeks you will have a test for diabetes and a check on your blood count. At approximately 36 weeks I take a vaginal swab to test that you are not a carrier of Group B Streptococcus, a potentially dangerous bacteria found in one in seven women. If your test is positive both you and your baby will receive antibiotics during labour and delivery. With this treatment, no baby should be severely affected by Group B Streptococcus. For more information on prenatal testing, please see below.
My holidays vary annually – if you wish to know what the dates I am away, please contact reception.
My weekend and holiday cover will be primarily shared with Dr Tom Cade however, sometimes there will be another Obstetrician covering.
Tom is Head of Diabetic Clinic at the Royal Women’s Hospital and delivers at Frances Perry House. He has experience in the management of normal and complicated pregnancies including multiple pregnancies. More details about Tom can be found in the ‘My Practice’ tab.
My weekends off extend from Friday afternoon until Monday morning. In my absence there will be 24 hour cover by one of the covering Obstetricians and you should feel free to contact them as you would contact myself. They can be contacted via the Call Service on 9387 1000.
When you commence having contractions, or if your membranes rupture (waters break), please telephone the Delivery Suite directly on 9344 5100. The midwife in Delivery Suite will advise you about the appropriate time to come into hospital. After you have been admitted, the midwife will phone me with a progress report and I will usually come to see you shortly afterwards. It is normal to have a small “show” of blood prior to the onset of labour. If the bleeding is more than a teaspoon full, or occurs before you are 34 weeks pregnant then you should contact me immediately.
In labour you will have a range of pain relief available to you. This will include gas, morphine, TENS and an epidural if necessary. Nothing will be given without your permission and pain relief will always be discussed with you before a decision is made. You have the choice to have an enema on admission to labour ward, although this is by no means a necessity.
Provided there are no medical complications, you may deliver in whatever position you find comfortable at the time. I do not routinely cut episiotomies unless it is necessary to prevent a large tear. Following delivery, you will then have an injection to help deliver the placenta more quickly in order to prevent excessive bleeding. I recommend strongly that your baby has an injection of Vitamin K (rather than the oral form) in order to prevent internal bleeding complications that affects approximately one in 1000 babies. If this injection is given, the complication is never seen.
Frances Perry House conducts childbirth education and early parenting classes. Information will be provided by Frances Perry House when you receive your hospital registration. Fees for private classes are usually covered by your health fund although there may be some out of pocket expense. I encourage both you and your partner to attend these classes, as they will prepare you better for labour, delivery, breast feeding and early parenting.
Several of these classes are available as an online program. Feedback from many of my patients has been very favourable for this format. There is still an opportunity for a hospital tour which I encourage.
Nausea and Vomiting
It is quite common to have some degree of nausea during the first trimester. This will generally begin at around six weeks, peak at around nine to ten weeks and gradually resolve between 12 and 14 weeks. Sometimes the nausea may be severe and persistent and occasionally associated with excessive vomiting. This is termed hyperemesis gravidarum (commonly known as ‘morning sickness’, although it can occur at any time throughout the day.) It is the normal increase in pregnancy hormones that causes these symptoms. Rarely, there may be an underlying cause to make the symptoms more severe. These situations may include a urinary tract infection, an overactive thyroid gland or a multiple pregnancy.
At its most extreme, vomiting can be so severe that hospitalisation is required and strong medication is necessary to prevent more serious complications. This is extremely unusual. If you are at the stage where you are vomiting more than twice a day, you should not hesitate to contact me, so you can avoid getting into this more serious situation.
There are many options to control the symptoms but there is virtually no treatment that will eliminate them completely. Treatment involves a combination of rest, dietary modification, vitamins, complementary therapies, conventional medicine and occasionally intravenous fluids.
There is a close association between the level of nausea and vomiting that you will experience and your level of tiredness. You should endeavour to rest as much as is practicable, although this may be quite difficult if you are working or have young children. Nevertheless, your symptoms will generally improve with increasing rest.
A well balanced and healthy diet, particularly avoiding fatty foods, will help. The mainstay of dietary modification is switching from the traditional pattern of eating three meals per day to eating multiple small meals. You should generally not go more than three to four hours without having something to eat. This “grazing” may involve continuously nibbling away at fresh fruit, dried fruit or dried biscuits or alternatively having five to six meals a day with a three to four hour interval. Over the years I have heard a multitude of different dietary suggestions and you should feel free to try any of them. Suggestions include abolishing either or both dairy and wheat products from your diet and replacing them with rice and soya based products. The “wet and dry” diet is popular. This involves alternating wet and dry foods. For example, toast for breakfast, a milkshake for morning tea, a sandwich for lunch, soup for afternoon tea, a normal dinner and then another milkshake before bed. Feel free to try anything that works for you.
Vitamin B6 (Pyriodoxine) has been the mainstay of treatment of nausea in early pregnancy for decades. It is extremely safe but has been improved recently with the introduction of Blackmore’s Morning Sickness Formula. This combines Vitamin B6 with a ginger extract. The combination works better than either Vitamin B6 or ginger alone. If you cannot tolerate swallowing the tablets then they are equally effective if you suck them. Please note that these are quite a different preparation to Blackmore’s Pregnancy and Breastfeeding Formula.
Acupuncture is wonderful for nausea and vomiting in pregnancy. Provided you have no contraindications to having acupuncture (this would include having hepatitis B or C, taking drugs to thin your blood or having a bleeding disorder) then acupuncture is to be strongly recommended. I can put you in contact with several excellent acupuncturists or alternatively you may locate an acupuncturist locally. Your General Practitioner may practise acupuncture. There is a range of other complementary therapies including aromatherapy, acupressure and Chinese herbal medicine, which you may find helpful.
If the alternatives above have not been of assistance then I may recommend that you take conventional medication. It is important to understand how drugs are classified according to their safety in pregnancy. In Australia drugs are categorised as A, B, C, D or X according to their safety in pregnancy.
Category A drugs have been taken by a large number of pregnant women for many years with no evidence of any adverse effects on the fetus ever having been reported.
Category B drugs, likewise, have never been shown to have any adverse effects but have only been taken by a limited number of pregnant women.
Category C drugs have been known to have effects on the fetus but these are not necessarily effects that may be harmful nor particularly relevant during the first trimester. For instance, it is best to avoid sleeping tablets late in the third trimester but they have no effects in the first trimester and therefore are safe to take.
Category D and Category X drugs are known to cause fetal malformations and must never be taken in pregnancy.
You can be assured that if I ever prescribe a drug for the treatment of any condition in pregnancy that I am perfectly comfortable with it’s safety. I will never prescribe a category D or X medication; almost always I will prescribe Category A and sometimes Category B drugs. If I ever prescribe a Category C drug I will explain why it is safe for you to use at that time but not safe to use later in pregnancy.
Nevertheless, I understand that there is a great reluctance for any women to take any medication in pregnancy and this is completely understandable. However, there are times when the benefits of taking medication outweighs any potential risk but it is always up to you.
This is frequently prescribed under the trade names of Maxolon and Pramin. This is a medication that needs to be taken three to four times a day and is best taken 30 minutes before you plan to eat. It is not uncommon to feel drowsy with Metoclopramide. You should stop using it immediately if you feel agitated or unusual while you are taking it.
This is generally provided under the trade name of Stemetil. It can be given as tablets or suppositories. It is generally taken three to four times a day in tablet form or once or twice a day in suppository form. It tends to be more sedative than Metoclopramide and again you should stop it immediately if you feel agitated while taking it. Prochloroperazine is given a category C medication only in relation to its use during the third trimester when it can cause irritability to your baby after delivery. It has no adverse effects during the first or second trimester and can be used very safely.
A variety of antihistamines have been recommended including Promethazine, Chlorpheniramine, Cyclizine, Cyproheptadine, Doxylamine and others. They have long been used very safely in pregnancy and are generally all either category A or B medication. Promethazine is a category C medication only because of its potential sedative effects on the infant so it should be avoided in the third trimester.
Antihistamines are widely used but are generally very sedating and will make it difficult for you to function normally.
The most effective antihistamine is Restavit (Doxylamine). This is a category A medication that is particularly sedating. It is ideally taken at bedtime to allow a good night’s sleep.
This is often provided under the trade name of Zofran. It is available in tablet or wafer form. Ondansetron is very expensive and there is no rebate available from the government to reduce the expense. I generally suggest the best form to buy it in is in the 8mg wafer form as these can be broken in half and sometimes half again to provide effective relief at a fraction of the cost. The wafers also have the advantage that they can be used even if you are vomiting because they can be placed under the tongue and absorbed effectively that way, eliminating worries about whether or not you have vomited the tablet.
Ondansetron should be reserved for severe vomiting that is resistant to all other forms of therapy. This is because of its cost and the more limited experience in relation to Maxolon or Stemetil. However, if I recommend it to you, you can be certain I am comfortable with its safety and that your symptoms are so severe that treatment with Odansetron is needed in order to reduce the risks of miscarrying your pregnancy.
Recent evidence has suggested that the use of high dose steroid therapy is effective for women who have intractable nausea and vomiting in pregnancy. This is reserved for the most severe forms of vomiting in pregnancy that would otherwise require long term hospitalisation. Prednisolone is a steroid (not the type that causes your voice to deepen and build muscle bulk) that will make you more prone to easy bruising, contracting infections, weight gain, increased appetite, bloating and insomnia. These are significant side effects that must not be disregarded. It is also not possible to simply discontinue treatment immeditately if it is ineffective. Treatment needs to be weaned over many weeks and so commencing Prednisolone is a long term commitment. However, it is remarkably effective at stopping the intractable vomiting that sometimes occurs and, if I do prescribe it, you can be assured that it is the most appropriate form of therapy for you in your circumstances.
If treatment with tablets and wafers is ineffective then it is usual for me to admit you to our Pregnancy Day Care Centre for intravenous rehydration. You will be surprised how much fluid is required to rehydrate you when you have had significant vomiting. Some women need to attend Day Care on an almost daily basis for some period of time before the symptoms are brought under control. If intravenous fluid therapy is required then many of the medications listed above can be given through the drip initially and then given orally or in wafer form after discharge. Some women find that daily visits to the Day Care Centre are too disruptive and prefer long term hospitalisation. This is very rare and you may find that after a few visits to Day Care the frequency of visits can be reduced and a visit once a month or twice a week for a “top up” is all that is necessary.
PRENATAL TESTING INFORMATION
One of the difficult issues to face in early pregnancy is the option for 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. They are optional but need to be considered carefully.
This information sheet provides a summary of the tests available and is intended to be a reminder of the issues that need to be considered. 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.
I have provided you with some information about the different tests available, and what they are looking for.
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
Genetic tests performed before or very early in pregnancy
Genetic carrier screening is now recommended 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 recommended 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 (recessive carriers).
Genetic Carrier screening can be done for just a few conditions, or part of an expanded panel of over 100 conditions. 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 $385.00 and you will be billed directly by the laboratory, Victorian Clinical Genetic Service (VCGS). These types of genetic tests are unfortunately not rebatable 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 at a cost of $220.00 (which is also not rebatable). If you or your partner are found to be carriers of CF, SMA or FRAX, I will organise immediate genetic counselling so 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.
Here is a brief description of these three main conditions tested:
Cystic fibrosis (CF) is an inherited condition affecting breathing and digestion and affects approximately 1 in 2500 babies. One in 25 Caucasians are carriers of CF. CF causes thick mucus which traps bacteria, resulting in recurrent infections that damage the lungs. Thick mucus in the gut also makes digestion of food difficult. Infants and children with CF require daily chest physiotherapy to clear mucus from their lungs, 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 many live to be 30, 40 or more. 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 cystic fibrosis. If the tests show that you have one copy of a CFTR gene change (mutation) for cystic fibrosis, then you are a carrier of this condition – but a couple is only at risk of having a child with CF if both parents are carriers of the condition. Carriers do not show any symptoms of CF but if you are a carrier of this condition your partner will be offered testing to clarify the risks for your future children.
Fragile X syndrome (FRAX) is the most common cause of inherited intellectual disability affecting around 1 in 4000 babies. Approximately 1 in 150 people are carriers of FRAX. People with FRAX can have developmental delay, learning difficulties, anxiety, autism and epilepsy. The features of FRAX vary from mild to severe with males more likely to be severely affected than females. Some, but not all females can also be severely affected. There is no cure for FRAX although some educational, behavioural and medical interventions can improve outcomes. Some females who are carriers of FRAX may have early menopause.
Fragile X syndrome is caused by an increase in the length of a particular gene known as the FMR1 gene, located on the X chromosome. Females have two X chromosomes, while males have one X and one Y chromosome. The Fragile X carrier test will tell whether you carry a change on your X chromosome, called a premutation. Women who carry a premutation may have a child with FRAX, but it is not certain. The VCGS test will detect about 97% of people who are carriers of FRAX. It is recommended that the female member of the couple is screened first with this combined test as FRAX testing is not necessary for the male partner. Female premutation carriers have a 1 in 2 chance of passing that X chromosome down, so if the female is a carrier, further investigation of the pregnancy is available to determine if the pregnancy will have Fragile X syndrome. Males can be FRAX carriers, but they cannot have a child with Fragile X syndrome. A male carrier’s daughters will all be FRAX carriers too, and they could be at risk of having children affected with FRAX in the future.
Spinal muscular atrophy (SMA) affects approximately 1 in 6000 babies. One in 40 individuals are carriers for SMA. There are two genes which cause SMA, called the SMN1 and SMN2 genes. SMA is a condition that effects 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.
The VCGS test will detect about 97% of people who are carriers of SMA. If the tests show that you have one copy of the gene change for spinal muscular atrophy, then you are a carrier of this condition – but a couple is only at risk of having a child with SMA if both parents are carriers of the condition. Carriers of SMA do not show any symptoms of the condition but if you are a carrier of this condition your partner will be offered testing to clarify the risks for your future children.
If you’d like to discuss these options further, I recommend you contact a genetic counsellor at Genetic Clinics Australia on 9528-1910 or www.geneticclinic.com.au. This is particularly important if you and your partner are related. If you have any Jewish ancestry, I recommend you contact Genetic Clinics Australia to find out which tests are most appropriate for you, such as Tay Sachs disease testing.
Prenatal tests performed at various stages throughout pregnancy
It is not possible to test pregnancies for every possible problem or medical condition but there are some conditions which can be detected during pregnancy.
Down syndrome (trisomy 21) is a condition in which an extra chromosome 21 is carried in each of the cells of the body. Instead of the normal 46 chromosomes there are a total of 47 chromosomes. The extra chromosome 21 results in intellectual disability of varying degrees and may cause problems with the heart, kidneys, bowel, eyesight or hearing. Although the chance of having a baby with Down syndrome increases with the mother’s age, babies with Down syndrome can also be born to younger mothers. The following table indicates the risk of having a baby born with Down syndrome. The risk estimation is based on the age of the mother at the expected time of delivery.
|Maternal Age||Risk of baby being born with Down Syndrome|
|25||1 in 1302|
|30||1 in 895|
|35||1 in 356|
|37||1 in 220|
|40||1 in 97|
|41||1 in 73|
|42||1 in 41|
|45||1 in 10|
Edward syndrome (trisomy 18) is a very serious condition in which an extra chromosome 18 is carried in each of the cells of the body. This condition occurs much less often than Down syndrome. Most pregnancies affected by Edward syndrome will miscarry. Those that continue may have a baby affected with serious heart, kidney or lung problems, which sadly do not survive very long. Many of the features of Edward syndrome may be apparent on ultrasound examination at 12 or 20 weeks. Like Down syndrome, the risk of Edward syndrome increases with maternal age.
The most common neural tube defects are spina bifida and anencephaly. Babies with spina bifida have an opening in the bones of the spine which may result in damage to the nerves controlling the lower part of the body. This can cause weakness and paralysis of the legs and sometimes inability to control the bowel and the bladder. In anencephaly, the brain does not develop properly and the baby will not survive. Around 1 in 750 pregnancies are affected by a neural tube defect if the mother has not been taking folate around the time of conception. This risk is dramatically reduced, although not completely eliminated, by taking folate.
Turner Syndrome is a condition where a girl inherits just one X chromosome instead of two, called monosomy X. Females with Turner syndrome therefore have only 45 chromosomes in every cell of their body, instead of the usual 46 (23 from each parent). Turner syndrome affects approximately 1 in 2000 girls born in Australia. There is great variability in the symptoms of Turner syndrome. Some girls with Turner syndrome are not diagnosed until puberty, while others might be symptomatic from birth. Many pregnancies with Turner syndrome will actually result in miscarriage. Characteristics of Turner syndrome in girls include short stature (~20cm shorter than average), infertility and oedema (swelling), which can sometimes be evident on ultrasound during pregnancy. The average intellectual performance of girls with Turner syndrome is usually within the normal range. Turner syndrome is not affected by increased maternal age, and can be a result of abnormal egg or sperm development. Girls with Turner syndrome usually have a normal life expectancy.
How reliable are these tests?
Sensitivity: the reliability of a test depends on its ability to detect a problem if it is there: this is known as the sensitivity of the test. This means that a test with 100% sensitivity will detect a problem every single time it is there, but if the sensitivity is 70% only 7 out of 10 babies who have this problem will be detected by this test.
False positives: the other important factor to consider in assessing the reliability of the test is the false positive rate. A test is considered to give a false positive result if it suggests there is a problem with the baby that is subsequently shown not to be there at all. Ideally a test would have a 0% false positive rate but in practice some positive results are incorrect.
Options for Prenatal 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.
Nuchal translucency (NT) scan (Between 11 and 14 weeks)
All babies have a small amount of fluid under the skin at the back of the neck. An excessive amount of fluid in this area is associated with a higher chance of having a baby with Down syndrome or other abnormalities such as heart or kidney problems. This amount of fluid can be measured by ultrasound and is called nuchal translucency, nuchal oedema or nuchal fold. If there is an excessive amount of fluid then further investigations will be recommended, usually in the form of invasive testing, such as a CVS. An ultrasound at this stage also has additional benefits including very accurate dating of the pregnancy, diagnosis of multiple pregnancy and the 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. In expert hands this technique has a sensitivity rate of 70% for detection of Down syndrome. The false positive rate is 5%. 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 fetal DNA found in the mother’s blood to detect Trisomy 21, Trisomy 18, Trisomy 13 and Turner syndrome and are alternatively referred to as cell free DNA tests. The test is >99% sensitive for the detection of these trisomies, and 92% sensitive for the detection of Turner syndrome. NIPT is known by several different names – the two most common are Harmony and Percept. I recommend all my patients consider NIPT as it is the best, non-invasive screening test for Down syndrome available.
Combined first trimester screening:
The combined first trimester test for Down syndrome involves combining the results of the nuchal translucency scan with the results of a blood test performed prior to the ultrasound. The combined first trimester test is specifically directed at detecting Down syndrome and Edward syndrome. Results of this testing are reported as low risk or increased risk. Increased risk results do not mean there is something wrong with the baby, just that additional testing can be performed to clarify the result. The sensitivity for detection of Down syndrome is over 90%. The false positive rate for this test is approximately 5%. Most babies with an increased risk on the combined first trimester test are completely normal.
Maternal serum screening (MSS):
Maternal serum screening is a blood test for pregnant women to determine if they 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 women who could be offered further testing such as ultrasound or amniocentesis. The results are usually available within one week and will be reported as low risk or high risk for each of these conditions. Low risk means that the risk of having a baby with Down syndrome, Edward syndrome or a neural tube defect is very low. High risk means that there is an above average risk of having a baby with one of these conditions but it does not necessarily mean that there is a problem with your unborn baby. It means that further tests should be considered to see if there is a problem. It is important to remember that most women with a high risk will go on to have a normal baby. The sensitivity of maternal serum screening for detection of Down syndrome is 80%. The sensitivity of maternal serum screening for detection of neural tube defects is more than 80%. The false positive rate for this test is 5% for each condition. While this test is Medicare funded, it is not the most accurate screening test for Down syndrome available and so I do not recommend it.
Chorionic villus sampling (CVS)
Chorionic villus sampling or CVS involves passing a needle into the placenta between 10 and 13 weeks gestation. A small amount of placental tissue is taken and a chromosome analysis is then performed by the pathology laboratory. Results take approximately ten working days to become available. Some ultrasound centres will offer you the option of FISH testing. This is a very rapid test for Down syndrome with the result being available the following day 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 detection of Down syndrome is virtually 100%. The only exception would be a technical problem growing the placental cells in the laboratory. In these circumstances an amniocentesis may be required later in pregnancy but this is exceptionally unlikely. The risk of miscarriage from the procedure itself is 0.2%. You must remember that there is a risk of spontaneous miscarriage at this gestation of approximately 2%. The total risk is therefore 2.2% although only a small proportion of this risk of miscarriage is actually as a result of the CVS test. The false positive rate for detection of Down syndrome is 0%.
Amniocentesis involves taking a small sample of amniotic fluid from around the developing baby at approximately 16 weeks gestation. Only a small amount of fluid is taken but this is enough for a full chromosome analysis to be performed. Results take approximately ten working days to become available. Some ultrasound centres will offer you the option of FISH testing. This is a very rapid test for Down syndrome with the result being available the following day at an additional cost. The risk of miscarriage from the procedure itself is approximately 0.1%. The risk of spontaneous miscarriage at this gestation is 0.5%. The total risk from the procedure and spontaneous miscarriage is 0.6%. 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 false positive rate for detection of Down syndrome is 0%.
This table summarises the sensitivity, false positive rates and risk of each test mentioned above.
|Test||Weeks pregnant||Detection of Down Syndrome||False positive rate||Risk from the test|
|NT test||12 to 13||70%||5%||0%|
trimester test||12 to 13||90%||5%||0%|
|MSS||14 to 19||80%||5%||0%|
|CVS||10 to 13||100%||0%||0.5% to 1.0%|
|Aminocentesis||15 to 19||100%||0%||0.5%|
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.
Please do not hesitate to clarify any of these issues with me if they are unclear. I can arrange for you to see a genetic counsellor if you would like more information. Genetic Counsellors are trained to help people understand the various genetic testing options available, coordinate testing, and to assist with decision making around the results.
General Advice and Precautions
Baths and spas are generally safe in pregnancy. The dangers occur from a jet of water entering the vagina (so be careful where you sit!) or from prolonged exposure to high temperatures (so keep the temperature moderate or the exposure short).
Most activities are safe in pregnancy but it is sensible to avoid parachuting, bungee jumping, water skiing and snow skiing.
Moderate exercise is fine, particularly if you have been used to it. Be careful with all activities that involve stretching; pregnancy loosens ligaments and injuries may easily occur. Strenuous exercise, particularly if repeated and prolonged, may have adverse effects on fetal growth. Please discuss with me if you have plans for vigorous exercise in pregnancy.
Contact sports need to be undertaken with caution. Babies are well protected but high level direct abdominal trauma is potentially harmful.
General pregnancy supplements such as Elevit or Blackmores pregnancy multivitamins, provided they contain iodine, are recommended for pregnancy.
It is possible to achieve the dietary requirements of most essential vitamins and minerals in a normal balanced diet. Unfortunately, this is not always easy in pregnancy when nausea, vomiting or dietary preferences may interfere. Additionally, iodine deficiency is a significant concern for pregnant women and can be avoided with these supplements.
I may recommend additional iron, folic acid, calcium, magnesium or vitamin D depending on your circumstances.
Sexual relations are generally safe at all stages of pregnancy. It is not unusual to have a small amount of bleeding after sexual intercourse. This is not a cause for concern unless the bleeding is either heavy or recurrent.
If you have a history of miscarriage you may prefer to abstain in the first trimester.
Female orgasm is completely safe.
There are many myths about sleeping positions for pregnancy. You may sleep on either your left or right side at all stages of pregnancy. It is best to avoid lying on your stomach from 12 weeks to avoid “squashing” your baby although the actual risk is very small. It is best to avoid lying on your back from 20 weeks so you avoid compressing the major blood vessels in your abdomen. This can lead to low blood pressure and fainting.
In practice, the risks to your baby are very small. If you wake up and find that you have been lying on your stomach or back do not panic! You will have done no harm; your body has done exactly what it should and woken you to allow a position change.
Vaccinations and Infections
Influenza, or the “flu” is a serious illness caused by the influenza virus. As there are multiple strains of this virus that change annually, it is necessary to have an influenza vaccination on an annual basis.
Pregnant women are particularly susceptible to influenza infection. It is a very serious illness that can cause severe pneumonia in the pregnant woman and, rarely, the loss of your unborn baby.
Influenza vaccination is:
• Recommended for every pregnant woman at all stages of pregnancy including the first trimester
• Essential if you have any other chronic illnesses such as diabetes, kidney or lung disease
• Free for pregnant woman and available at your General Practitioner (GP)
• The best way you can protect yourself and your unborn baby against influenza
Important facts about influenza vaccination:
• The influenza vaccination does not give you influenza
• The influenza vaccination will protect you for 12 months
• An influenza vaccination during pregnancy will also protect your baby from influenza for the first six months of life.
Please disregard the myths and misconceptions that you may hear from friends, relatives or on the internet. Most of this advice regarding infuenza vaccination is simply incorrect.
If you have any questions about the vaccination please do not hesitate to ask me.
Toxoplasmosis is a rare but severe infection that can complicate pregnancy. It is transmitted by the handling of cat faeces.
Transmission can be prevented by simply avoiding the handling of cat litter. Gardening without gloves is also a risky practice to be avoided.
To avoid this risk, simply ensure you wash your hands thoroughly if you do happen to do either of these activities.
Whooping cough, or pertussis, is a highly contagious disease caused by the bacteria Bordetella pertussis and is spread by droplets from coughing and sneezing. Susceptible people are those who are either unvaccinated or have waning immunity since childhood vaccines. Whooping cough is particularly serious in infants under 12 months of age, while older children and adults usually have a milder disease.
Symptoms may vary for different ages but first symptoms are usually similar to a cold. Severe cases develop sudden attacks of repetitive coughing and often a characteristic ‘whoop’ as the person gasps for breath. Not all cases get the ‘whoop’. Babies may have pauses in breathing (apnoea). Vomiting often follows a coughing spasm. A person with whooping cough is infectious for up to three weeks after they start coughing. The cough may last for months.
Whooping cough has tragically resulted in he deaths of several babies in Victoria in recent years. Babies are at risk from birth as no pertussis protection is passed from mother to newborn infant. Complete immunisation of children and new parents remains the most effective measure to control whooping cough. Pertussis vaccination is offered as part of the government funded immunisation program for children at two, four, six months, at four years and in year 10 of secondary school (or 15 years of age).
People become immune either through pertussis immunisation or by catching the disease itself, but protection is not life long and begins to fade after 6-10 years. Sometimes immunised people still contract pertussis, but they are likely to have a less severe illness and may not have the typical whoop.
Adult pertussis booster vaccines (combined with diphtheria and tetanus) are recommended for all women in the 3rd trimester of pregnancy, regardless of when their last vaccine was administered, Addtionally, partners, family and anyone else who will have contact with your baby need to have a booster every ten years.
Boostrix® is the recommended vaccine and is provided free to parents of new babies. Whilst pertussis booster vaccine is strongly recommended for the other groups outlined, it is not funded. Boostrix® is completely safe when administered in pregnancy.