Welcome to the 2F Prenatal Diagnosis Clinic (PND)

Transcription

1 Welcome to the 2F Prenatal Diagnosis Clinic (PND) At your appointment today, you will first meet a Genetic Counsellor, who will review your family and medical history with you. She will also discuss the reason you were referred. She will provide information about the findings in your pregnancy, and any genetic implications. You will also meet the Maternal Fetal Medicine (MFM) specialist, who will review your recent ultrasound and the issues concerning your pregnancy. Together, the team will make a plan for your care. This may include asking other health professionals or specialists to see you. To assist us, please complete the attached personal and family history questionnaire. Please note, this is a teaching hospital. We may have residents, medical students, midwifery students, or genetic counselling interns participating in patient care. If you have any concerns about the role of learners in your care, please speak with a staff member. The information in this booklet is intended to accompany a consultation in the PND clinic. Some of the information may not apply to every pregnancy.

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3 Contact Information Main reception (905) ext General inquiries, directions, confirm or change an appointment Fax number (905) Genetic Counsellors (905) ext Marlene Huggins Sarah Ruddle Natasha McNamee Laura Wallace Gina Cowing Kate Gardiner Physicians Dr. Bryon DeFrance Dr. Patrick Mohide Dr. Stephanie Winsor Dr. Sarah McDonald Dr. Michelle Morais Table of Contents Welcome and Introduction 1 Learning About Prenatal Ultrasound 11 Information about Chromosomes 2 Nuchal Translucency 12 Information about Down syndrome 2 Ultrasound Soft Signs 13 Table of Age Related Risks 3 Ultrasound Abnormalities 14 Learning About Prenatal Diagnostic Tests 4 Prenatal Testing for Twins 15 Summary Chart of Diagnostic Testing 5 If you are having Amniocentesis or CVS 16 Information about Amniocentesis & CVS 6 If you are Rh negative 16 Risks of testing and test results 7 Learning about Abnormal Results 17 Learning about Prenatal Screening 8 Decisions about Abnormal Results 18 Summary Chart of Prenatal Screening 9 Information about Folic Acid 19 Non-Invasive Prenatal Testing (NIPT) 10

4 Information about the Prenatal Diagnosis Clinic This clinic will help you learn about findings in your pregnancy that may affect the health of your baby. There are options for different types of tests that can be done to learn about your baby s condition or the chance for some kinds of health problems. Tests that can tell you for certain if your baby has a genetic problem are called prenatal diagnostic tests (pages 4,5,6,7). Prenatal Diagnostic testing is available for all pregnant women who have an increased chance of certain health problems for the baby (from blood tests or ultrasound findings or previous history). Tests that can tell you the chance that your baby has certain health problems are called prenatal screening tests (pages 8,9,10). Prenatal Screening is available for all pregnant women of any age regardless of any findings or previous history. It is your choice whether to have any screening or diagnostic tests of your pregnancy. To help you make this decision, your doctor or midwife may discuss the tests that are available to you. The Genetic Counsellor in the PND clinic can review the information in this booklet that relates to you. Please feel free to ask questions at any time. Take the time you need to understand what the tests can and cannot tell you. We know that decisions about testing your pregnancy can be stressful for you and your family. Our health care team is available to support you. As well as the Genetic Counsellor, you will meet with a Maternal Fetal Medicine Specialist (specialist obstetrician). Other specialists such as a social worker are also available to you. If you choose to have any screening or diagnostic tests, we will make the arrangements. We will explain and discuss the results when they are ready, and help you decide on the next steps in your care. During your initial visit to the Prenatal Diagnosis Clinic, you will: Complete a review of your family history and medical history. Meet with a genetic counsellor to discuss your pregnancy. Meet with a doctor to review the findings and the plan of care. pg. 1

5 Information about Chromosomes Chromosomes carry genetic information (the instructions for growth and development). The complete set of 46 chromosomes is needed for normal growth and development. Females have two X chromosomes, while males have one X and one Y chromosome. This is a picture of normal female chromosomes. There are two copies of each chromosome, with one copy inherited from the mother and one copy inherited from the father. Information about Down Syndrome Down syndrome results from having an extra copy of chromosome number 21 (trisomy 21). The extra chromosome is present from conception. Parents cannot cause Down syndrome by anything they did or did not do. People with Down syndrome can have a range of mental retardation. There is no way to predict the severity before birth. About one-third (1/3) to one-half (1/2) of children with Down syndrome have heart defects or other medical problems, which may benefit from surgery. Most persons with Down syndrome live with their families or in a group home environment. This is a picture of chromosomes from a person with Down syndrome. There are three copies of chromosome number 21. pg. 2

6 Age Related Risks for Chromosome Abnormalities The chance of having a baby with a chromosome abnormality increases with the mother s age. The father s age does not affect the chance for the baby to have a chromosome abnormality. The table below shows the chance of having a baby with a chromosome abnormality at different ages (the age of the mother when a baby is due): Maternal Age Chance of Down syndrome Total chance of a chromosome abnormality 20 1/1650 1/ /1250 1/ /900 1/ /625 1/ /500 1/ /385 1/ /300 1/ /225 1/ /175 1/ /135 1/ /100 1/ /80 1/ /60 1/ /50 1/ /40 1/ /30 1/ /23 1/ /18 1/ /14 1/9 49 1/11 1/7 Chance of Down syndrome refers to the chance for the baby to have Down syndrome, which is caused by the baby having an extra copy of chromosome 21 (trisomy 21 see page 2). Total chance of a chromosome abnormality refers to the chance for the baby to have any chromosome problem, including trisomy 21, trisomy 18, or trisomy 13, for example. When a baby has trisomy 13 or 18, there are usually very serious birth defects, and these babies rarely survive. Some other chromosome abnormalities may have little effect on the baby s growth and development. But most chromosome differences (extra or missing DNA) can be expected to affect both physical and intellectual outcomes. pg. 3

7 Learning about prenatal diagnostic tests Prenatal diagnostic tests examine the baby s chromosomes. These tests will tell you for certain if the baby s chromosomes are normal or abnormal. These tests are only used if there is a reason to suspect a chromosome abnormality, such as: There are abnormal ultrasound findings (pages 11-14) The prenatal screening (IPS, FTS, MSS) reported an increased chance of Down syndrome (pages 8 and 9) The diagnostic tests that are commonly used are: Amniocentesis (page 6): testing the chromosomes / DNA of the baby s cells, which are found in the fluid surrounding the baby. Chorionic Villus Sampling (CVS) (page 6): testing the chromosomes / DNA of cells from the developing placenta (afterbirth). If the result of amniocentesis or CVS is normal, it means the baby does not have Down syndrome, trisomy 18 or trisomy 13. If all 23 pairs of chromosomes were examined, then a normal results means there was no extra or missing DNA reported. Having a normal test result does not guarantee the birth of a normal baby. There are health problems that a baby could have, which are not detected by amniocentesis or CVS. In Ontario, approximately 2 to 3 % of all babies are born with a birth defect; only some of these are caused by chromosome abnormalities. If the result of amniocentesis or CVS is abnormal, it means the baby has a chromosome difference. This might be Down syndrome, or it might be something else, which your Genetic Counsellor will tell you about. Information about abnormal results is on pages 17 and 18. Most chromosome differences will affect the baby s growth and development, both physically and mentally. Some chromosome differences may be inherited from one of the parents, and the baby could still be healthy. Your doctor or genetic counsellor will discuss whether any other tests should be done, such as chromosome testing of the baby s mother and father, or a detailed ultrasound to check the baby. More information about prenatal ultrasound can be found on pages 11 to 14 of this booklet. pg. 4

8 Summary of Prenatal Diagnostic Testing Options A diagnostic test will confirm or rule out a chromosome abnormality. Type of procedure CVS Amniocentesis How is it done? Transcervical with ultrasound Transabdominal with ultrasound Transabdominal with ultrasound When is it done? 11 to 13 weeks 11 to 14 weeks After 15 weeks Background risk of miscarriage (with no procedure done) 3-5 % 3-5 % 2 % Added risk of miscarriage (due to procedure) 1-2 % 0.5 1% 0.25 % Chance of inconclusive result 1 2 % % Type of testing done QFPCR (chromosomes 13, 18, 21, X and Y) Full chromosome testing if needed AFP testing for spina bifida (amniocentesis only) Special genetic testing if needed Length of time for results 2-5 days for QFPCR 2-3 weeks for most other genetic tests Accuracy of test results % Small risk of placental mosaicism (when the cells in the CVS are not the same as the fetal cells, about 1-2% of the time) Greater than 99 % pg. 5

9 Information about Amniocentesis What is amniocentesis? This is a procedure that removes a small amount of fluid from the sac of fluid around the baby (amniotic sac). The amniotic fluid contains cells from the baby. The baby s cells and the fluid can be tested. How is amniocentesis done? A specially trained obstetrician does the procedure, usually between 15 and 20 weeks of pregnancy. An ultrasound scan confirms the position of the baby and placenta. The doctor uses the ultrasound to find a safe spot to insert a thin needle through the mother s abdomen, into the amniotic sac. A small amount of amniotic fluid is removed through the needle, then the needle is taken out. The fluid sample is sent to the laboratory for testing. Ultrasound probe Amniotic fluid Fetus Placenta Uterus Sample of amniotic fluid Information about Chorionic Villus Sampling (CVS) What is CVS? This procedure removes a small amount of tissue from the developing placenta (afterbirth). Cells from the placenta are genetically the same as the baby in most cases. How is CVS done? A specially trained obstetrician does the procedure, usually between 11 and 13 weeks of pregnancy. An ultrasound scan confirms the position of the baby and placenta, and helps to find a safe way to do the procedure. There are two ways to perform CVS: A. Transabdominal CVS: A thin needle is put in through the mother s abdomen, into the developing placenta. B. Transcervical CVS: A thin instrument is inserted through the cervix (birth canal) and into the developing placenta. A small tissue sample is sent to the laboratory for testing. A B pg. 6

10 What information can amniocentesis or CVS give? QFPCR: This is a quick test for Down syndrome, trisomy 13 and trisomy 18, as well as the X and Y chromosomes (which will tell if the baby is male or female). This test will tell you if there are extra or missing chromosomes, for numbers 21, 18 or 13 as well as the X or Y. Results are available in 2 to 5 days. AFP testing for spina bifida: The amount of alpha-feto-protein (AFP) can be measured in amniotic fluid but not in CVS samples. Higher than normal amounts of AFP can be due to spina bifida or other conditions. For women having CVS, the AFP can be measured in a blood test after 15 weeks. Results are available in 2 to 5 days. Chromosome testing: The chromosomes or DNA from the amniocentesis or CVS is examined for extra or missing pieces of all 23 pairs of chromosomes. Results are available in 2 to 3 weeks. This testing is either a karyotype, which examines the whole chromosomes and large pieces of chromosomes, or a chromosomal microarray, which examines smaller pieces of DNA from all the chromosomes to see if anything is extra or missing. Other genetic testing: Depending on your history or the findings in your pregnancy, specific genetic tests may be done for many rare disorders. The genetic counselor will talk to you about whether these tests are needed. Timing for results depends on the test ordered. What are the risks of amniocentesis or CVS? Miscarriage: For amniocentesis, there is a risk of between 1 in 200 (0.5%) to 1 in 400 (0.25%) to have a miscarriage due to the procedure. For CVS, there is a risk of about 1 in 100 (1%) to have a miscarriage following the procedure. Cramping, bleeding or fluid leakage: After amniocentesis, some women have cramping or fluid leakage from their vagina. After CVS, some women have cramping or bleeding from their vagina. This may last a few days. It may be helpful to limit your activity and to consider bedrest for 24 hours if you are concerned about any of these symptoms. Discomfort: Most women say amniocentesis and CVS are uncomfortable, but not more painful than having a blood test or a PAP test. No freezing is used, as the needle for freezing would give the same discomfort as the one used for amniocentesis or CVS. pg. 7

11 Learning about prenatal screening ( Multiple marker screening ) Screening uses blood testing and ultrasound to tell you what is the chance for the baby to have certain health problems. This can help you decide whether to do further (diagnostic) testing. The best prenatal screening uses ultrasound to measure nuchal translucency (NT) at the back of the fetal neck. More information about NT can be found on page 12. The screening tests that are commonly used are: First Trimester Screening (FTS): a combination of NT ultrasound with biochemical testing of a pregnant woman s blood at weeks, to tell the chance of Down syndrome or trisomy 18. Second Trimester Screening (MSS): biochemical testing of a pregnant woman s blood at weeks, to tell the chance of Down syndrome, trisomy 18, or spina bifida (see page 14). Integrated Prenatal Screening (IPS): a combination of NT ultrasound and biochemical blood testing at weeks, and more blood testing at weeks, to tell the chance of Down syndrome, trisomy 18 or spina bifida (see page 14). If your prenatal screen is positive, it means there is an increased chance that the baby has a specific health problem. Further testing can be done to find out for sure. Most of the time, when the result is positive, the baby does not have any health problem. This is called a false positive. Screen positive for Down syndrome means that the chance of the baby having Down syndrome is higher than expected. You have the option to do amniocentesis or CVS to find out for sure if the baby has Down syndrome. Screen positive for trisomy 18 or 13 means that the chance of the baby having trisomy 18 or 13 is higher than expected. A baby with trisomy 18 or 13 has an extra copy of chromosome 18 or 13, which causes severe abnormalities. You have the option to do amniocentesis or CVS to find out for sure if the baby has trisomy 18 or 13. Screen positive for open spina bifida (OSB) means that the chance of the baby having spina bifida is higher than expected. The best way to find out if a baby has spina bifida is to have an ultrasound to look closely at the baby s spine. If your prenatal screen is negative, it means the chance of the baby having one of these health problems is low. Most women with a screen negative result will have a normal baby, but (rarely) a baby with Down syndrome can be born after a negative screen result. This is called a false negative. Having a negative screen result does not guarantee the birth of a normal baby. Some health problems are not detected by prenatal screening. In Ontario, about 2 to 3% of all babies are born with a birth defect. Only some of these defects are detected before birth. pg. 8

12 Summary of Prenatal Screening Options Screening provides information about the chance of an abnormality; diagnostic testing would be needed to confirm if there truly is an abnormality. Screening Option First Trimester Screening (FTS) Integrated Prenatal Screening (IPS) Second Trimester Screening (MSS) How is it done? NT ultrasound and blood test at 11 to 14 weeks of pregnancy Step 1: NT ultrasound and blood test (11-14 weeks) Blood test at 15 to 20 weeks of pregnancy Step 2: blood test (15 to 18 weeks) Length of time for results 2 to 5 days 2 to 5 days after step 2 2 to 5 days What information will it give? Chance of Down syndrome or trisomy 18 Chance of Down syndrome, trisomy 18 or spina bifida (OSB) Chance of Down syndrome, trisomy 18 or spina bifida (OSB) Detection Rate (what portion of pregnancies with the condition will screen positive) Down syndrome: 83% Trisomy 18: 91% Down Syndrome: 88% Trisomy 18: 90% OSB: 85% Down Syndrome: 81% Trisomy 18: 60-70% OSB: 85% False positive rate (what portion of normal pregnancies will screen positive) 5 % 3 % 5 % What diagnostic tests are available if screen is positive? Amniocentesis; possibly CVS depending on gestational age Amniocentesis Amniocentesis pg. 9

13 Non-Invasive Prenatal Testing (NIPT) This is a new way to screen high risk pregnancies for the most common chromosome problems. This test looks at pieces of fetal or placental DNA in the mother s blood. This test is available for singleton and twin pregnancies. How is it done? When is it done? Risk of miscarriage? NIPT Blood draw Anytime after 10 weeks No added risk of miscarriage Type of testing done Chromosomes 13, 18, 21 Chromosomes X and Y (Gender not available for twin pregnancies) Length of time for results 10 business days Detection rate 99% Down syndrome (Trisomy 21) 98% Trisomy 18 80% Trisomy 13 99% X and Y False positive rate Less than 0.1% Chance of inconclusive result 5% no result 1% inconclusive result Cost Approximately $800 May be covered by OHIP if there are abnormal findings in the pregnancy, previous abnormal pregnancy or maternal age >40 For women who receive a positive (abnormal) result of NIPT, we recommend this be confirmed by amniocentesis. For women who receive a negative (normal) result of NIPT, no further testing is recommended in most cases. Harmony Prenatal Test from Ariosa Diagnostics is offered in Ontario through Gamma-Dynacare labs. For more information, please see their website at: Panorama Prenatal Test from Natera is offered in Ontario through LifeLabs. For more information, please see their website at pg. 10

14 Learning about Prenatal Ultrasound What is Ultrasound? High-frequency sound waves are directed at the tissues in your abdominal area. These sound waves bounce off the curves and variations in your body, including the baby and the placenta. The sound waves are translated into a pattern of light and dark areas creating images of the baby. Ultrasound does not involve radiation, nor does it use dyes that need to be injected or swallowed. Many factors affect the quality of ultrasound examinations. These include: * The length of time for the examination * The quality of the equipment * The experience of the ultrasound technician * The mother s abdominal wall thickness * The baby s size, position, and activity The Society of Obstetricians and Gynaecologists of Canada (SOGC) recommends that all pregnant women be offered a full obstetrical ultrasound at 18 to 20 weeks in pregnancy. The main purpose of this ultrasound is to look at the baby s growth and development. At this time of pregnancy, the baby is big enough to be able to see all the parts (head, chest, heart, lungs, abdomen, stomach, kidneys, and limbs) clearly in most cases. If your doctor has not discussed an ultrasound booking for 18 to 20 weeks of your pregnancy, you may wish to ask to have this done. You must remember, though, that a normal ultrasound at 18 to 20 weeks does not rule out all abnormalities. Prenatal Ultrasound and Down Syndrome Down syndrome is a chromosomal abnormality. Ultrasound cannot see chromosomes. Therefore, ultrasound is not the best test to find out if a baby has Down syndrome. Much of the time, when a baby has Down syndrome, ultrasounds are normal. However, some babies with Down syndrome have differences that may be detected by ultrasound. For some women, ultrasound may be helpful in deciding whether or not to have amniocentesis, but it is important to remember that a normal ultrasound does not rule out Down syndrome. pg. 11

15 Learning about Nuchal Translucency What is Nuchal Translucency (NT)? NT is an ultrasound measurement of a small fluid collection normally found within the skin at the back of the baby s neck between 11 and 14 weeks of pregnancy. A person specially trained in this type of ultrasound must do the NT measurement. The NT measurement can be combined with mother s age and blood testing for prenatal screening for Down syndrome and trisomy 18 (see pages 8 and 9). Increased NT means the measurement is bigger than expected (usually more than 3mm). This means there is a higher than usual chance for the baby to have a chromosome problem or some birth defects. Often, the increased NT is the only problem the baby has. If that is the case, the swelling usually disappears later in the pregnancy, and the baby will develop normally. Sometimes, increased NT is the first sign that the baby that the baby has a chromosome problem or another health problem, which may or may not be found before birth. It might be helpful to complete prenatal screening or test the baby s chromosomes by amniocentesis or CVS. A detailed ultrasound should also be done at approximately 19 weeks of pregnancy, to check the baby s anatomy carefully. pg. 12

16 Prenatal Ultrasound Findings - Soft Signs An ultrasound soft sign or marker (risk factor) is a finding on ultrasound that is not a birth defect, but suggests the possibility that the baby has some kind of underlying condition such as Down syndrome. These findings can be seen in completely healthy babies. Finding a soft marker does not diagnose a baby with a condition such as Down syndrome. In fact, most babies with soft markers will be completely healthy. If your baby is found to have a soft marker, your doctor or genetic counsellor can provide information about that marker, the associated disorder and any testing that is available. If there is no underlying condition, soft markers generally do not cause any harm to the baby or the mother. When ultrasound shows a soft marker, it is important to review the pregnancy history for other risk factors. These other risk factors include mother s age, family history of birth defects, and results of prenatal screening. You may wish to discuss the risks and benefits of diagnostic testing such as amniocentesis (see page 6). Some examples of soft signs are: Increased nuchal fold (NF): a thickened area at the back of the baby s neck. This does not affect the baby s health, but it suggests an increased chance of Down syndrome and sometimes other birth defects. Short nasal bone (NB): small bone in the baby s nose. This does not affect the baby s health or the facial appearance after birth, but it may mean there is an increased chance of Down syndrome. Choroid plexus cysts (CPC): small fluid bubbles within the choroid (a spongy tissue in the baby s brain). These do not affect the brain at all, but suggest there may be an increased chance of birth defects due to trisomy 18, a very severe chromosome problem. Echogenic intracardiac focus (EICF): an area in the baby s heart that appears more white than usual with ultrasound. This does not affect the function of the heart, but it suggests there may be an increased chance of Down syndrome. Echogenic bowel: areas of the baby s bowel that appear more white than usual with ultrasound. This rarely affects the function of the bowel, but can be associated with Down syndrome, some viral infections and some other genetic problems such as cystic fibrosis. pg. 13

17 Structural Fetal Abnormalities A structural fetal abnormality is usually a health concern for the baby. Some can be relatively minor, and some can be life-threatening. In most cases, it is recommended to follow the pregnancy closely and deliver the baby in the Medical Centre. If there are abnormal or suspicious findings on your routine ultrasound, you may be referred for a more detailed ultrasound. The doctors and counsellors of the Prenatal Diagnosis Clinic can talk to you about the findings and what they might mean for the baby. Sometimes, a 3D ultrasound will be useful, but that will depend on the findings. Some examples of common fetal abnormalities are: Cleft lip and palate (CLP): a separation of the two sides of the lip, sometimes also including an opening in the roof of the mouth. Most babies with this condition need surgery after birth, and most will be completely well after that. Abdominal wall defect (omphalocele, gastroschisis): an opening on the front of the abdomen, which allows some of the organs to form outside of the body. Some babies will have no other problems, and they will have surgery to repair the opening after birth. Some babies will have other birth defects or chromosome problems, which may be minor or very serious problems. Heart defect: an abnormality of the heart structures or the blood vessels near the heart. Some babies will have no other problems, but they may need surgery or medical treatment after birth. Some babies will have other birth defects or chromosome problems, which may be minor or very serious problems. Spina bifida: a birth defect of the spine which leads to varying degrees of damage to the spinal cord and central nervous system. Most babies will have surgery to repair the opening after birth. Spina bifida usually results in some physical handicap, and there may be mental handicap as well. pg. 14

18 Learning about Prenatal Testing for a Twin Pregnancy Both diagnostic testing and screening are available, but there are important differences when you are carrying more than one baby. Screening (see pages 8 and 9) Second Trimester screening can be used to find out the chance of spina bifida, but it cannot tell the chance of Down syndrome in a twin pregnancy. First Trimester Screening can be used to find out the chance of Down syndrome in a twin pregnancy. The nuchal translucency (NT, page 12) is measured for each baby, and the NT result is combined with the mother s age related risk, to tell you what is the chance of Down syndrome or trisomy 18. Diagnostic Testing (see pages 4, 5, 6, 7) Amniocentesis (page 6) can be done in a twin pregnancy, but it is necessary to sample the fluid in each amniotic sac in order to check the number of chromosomes for each baby, unless the twins are known to be identical. The risk of the amniocentesis procedure increases with the number of needle insertions done. Therefore, if you have amniocenteses for each baby, the risk of miscarriage is up to 1%. There is a small risk that the fluid around one of the babies may be sampled twice and the other baby may not be tested at all. CVS (page 6) is more difficult in a twin pregnancy and it is not always possible. Non-Invasive Prenatal Testing (NIPT) (see page 10) This blood test looks at fetal / placental DNA in maternal blood, in order to test for trisomy 13, trisomy 18 and trisomy 21 (Down syndrome). It is not possible to find out the gender in a twin pregnancy using this test. What if one baby is normal and the other is abnormal? In most cases, results will be normal for both babies. However, it is possible to have abnormal findings in one baby but not in the other. In a twin pregnancy with one healthy baby and one baby with an abnormality, the parents may face difficult decisions about the pregnancy. The doctors and counsellors of the Prenatal Diagnosis clinic can discuss this in more detail. pg. 15

19 If you are having amniocentesis or CVS Before your procedure: You may eat your breakfast as usual. For CVS, you must have a very full bladder. For amniocentesis it is not necessary to have a full bladder. If possible, someone should come with you who can drive you home after the procedure is done. We suggest you allow at least one hour for the procedure visit. After your procedure: Limit your activities for the first 24 to 48 hours. This means: rest, no heavy lifting (including small children!), no strenuous exercise, and no sexual intercourse ( if you had CVS). Some women will have cramping and increased vaginal discharge. This is usually mild, and should get better after the first day. Call your doctor or midwife if you have heavy vaginal bleeding, watery vaginal discharge, severe pain or cramping, fever of 38 C or F, or any changes with your pregnancy that are of concern. If you are unable to reach your doctor or midwife, please call Labour and Delivery at McMaster. Call (905) If you are Rh negative: Your doctor will be asked to send us a copy of your blood type and antibody screen, which is routinely done during pregnancy. This blood testing may need to be repeated if it was more than one month before the CVS or amniocentesis. You will be given an injection of Rh gamma globulin (WinRHO) to protect you from possible antibody production. Although this is normally done at 28 weeks of pregnancy, it is also done after an amniocentesis or CVS, or if you have a significant amount of bleeding at any time. You will likely have the WinRHO injection again at 28 weeks; you should discuss this with your doctor or midwife. When the results are completed: We will call and tell you the results as soon as we receive them. If the result is normal, we will tell you on the phone or leave you a message. There is no need for a follow up visit. If the result is abnormal, we will talk briefly on the phone, and book an appointment for genetic counselling as soon as possible. We will tell you whether your baby is a boy or a girl, if you ask us for this information. The laboratory report will be sent to your doctor. pg. 16

20 Learning about Abnormal Results If your prenatal screening result is positive (MSS, FTS, or IPS): Remember that this does not mean an abnormality has been diagnosed; it only means the chance of an abnormality is increased. You have the option of further testing, in order to know for certain whether your baby has Down syndrome, trisomy 18, or spina bifida. Further testing for Down syndrome or trisomy 18 / 13 is available by NIPT (see page 10). Diagnostic testing is done by amniocentesis (page 6) or by CVS (page 6). Further testing for spina bifida is done by ultrasound (page 11 to 14). If your NIPT result is abnormal: We will call you to tell you the result as soon as we receive it from the laboratory. Remember that NIPT is still considered screening, and it is recommended to have further testing to find out for certain about the baby s chromosomes. In most cases, this will be done by amniocentesis (see page 6). You have the option to meet with the genetic counsellor as soon as possible to discuss the next steps. If your amniocentesis or CVS result is abnormal: We will call you to tell you the result as soon as we receive it from the laboratory. We will discuss the result briefly on the telephone. We will book an appointment for you to meet with the genetic counsellor as soon as possible. If your ultrasound is abnormal: We will discuss the findings with you after the ultrasound is completed. Sometimes, more tests will be needed in order to fully understand what the ultrasound finding means for your baby s health. Remember that some ultrasound findings are only markers, and the baby may still be healthy (page 13). You may find it helpful to meet with other health care specialists who can help you understand your baby s condition. We will provide you with written information about the abnormality identified, and information about decision-making. pg. 17

21 Decisions about Abnormal Results Doctors, nurses, genetic counsellors, and social workers are available to help you with obtaining information to make the best decision for your situation. It is very important to take your time before making any decision about the pregnancy. We will help you to get the information you need to be comfortable about what you decide. When you come in to the clinic to discuss abnormal results: We will review the laboratory testing and results, or any abnormal ultrasound findings. We will discuss the problem, and how it will affect the baby. We will arrange for you to meet with a specialist who cares for children with that condition, if that would be helpful for you. We will arrange for you to meet with the social worker, if you wish. We will discuss a plan for your continued care. pg. 18

22 Consideration for future pregnancies Information about Folic Acid Folic Acid is one of the B vitamins required for good health. It is found mainly in green leafy vegetables, beans, asparagus, citrus fruits and juices, whole grain foods and liver. It has also been added to some foods such as enriched breads, pastas, rice and cereals. However, it is difficult to get enough folic acid through diet alone. You can make up the difference by taking a multivitamin or folic acid supplement. All women can decrease the chance of having a baby with spina bifida or other birth defects by taking folic acid before becoming pregnant, and for the first three months of any pregnancy. To reduce the chance of birth defects, folic acid must be taken before conception and for the first several weeks of pregnancy. It is not enough to start taking folic acid once you discover you are pregnant - by that time your baby has already been developing for many days or weeks. pg. 19