Antenatal Care Your Pregnancy Guide
Here you can find information about screening for chromosomal abnormalities, planned appointments during your pregnancy, important fetal ultrasound examinations and childbirth classes.
The stage of pregnancy (week of gestation) at which each examination needs to be performed, as well as the time of the planned appointments, are only indicative.
It is possible that the timing of pregnancy appointments change, depending on the individual case.
This is the time of the first ultrasound examination in pregnancy. The doctor checks that there is an intrauterine gestational sac and that there is no evidence of an ectopic pregnancy. In the majority of cases, fetal heart activity can be assessed from 7 weeks onwards.
During weeks 7-10 of gestation a number of examinations are performed, in order to ensure that the pregnancy starts under optimum conditions.
- Full blood count (FBC), iron and ferritin levels: if you do not have recent results it is recommended that you repeat the tests. These tests show if you are anaemic (you have low haematocrit and/or low iron) and you need treatment during the pregnancy. Also, they assess the platelet count that is important for the coagulation of the blood.
- Haemoglobin electrophoresis: this test aims to assess for the presence of haemoglobin disorders, such as beta-thalassaemia or sickle cell disease trait.
- Rubella antibodies (IgM and IgG): Rubella is a rare disease nowadays due to the widespread availability of immunization. However, if you are not immune we recommend that you get the vaccine after delivery. In case a woman gets infected with rubella in the 1st trimester of pregnancy, it is teratogenic and can cause fetal abnormalities such as eye disorders (i.e. cataract), deafness, heart abnormalities and mental retardation.
- Cytomegalovirus (CMV) IgM and IgG. CMV infection can cause fetal hepatomegaly and splenomegaly, microcephaly and mental retardation (similar to toxomplasmosis). It is a serious condition and no treatment is available.
- Toxoplasma (Toxo) IgG and IgM: Toxoplasma can be transmitted from an infected cat. If the infection occurs in the 1st trimester, it could cause intrauterine death or congenital toxoplasmosis that is characterized by microcephaly and mental retardation. If the infection occurs in the 3rd trimester, the neonate could be asymptomatic or it could develop chorioretinitis. Antibiotics can be used to treat toxoplasma infection.
- Thyroid function tests (FT3, FT4, and TSH): thyroid disease is common in women. Uncontrolled thyroid function is associated with miscarriages.
- Hepatitis B (HbsAg) and Hepatitis C (HCV): although rare, they can be associated with serious health sequelae
- Syphilis (VDRL)
- AIDS (HIV I-II)
- Blood tests for glucose, urea and creatinine levels
- G6PD: this is an enzyme that takes part in the metabolism of the red blood cells. Some individuals lack G6PD and if they take certain medications they might develop a number of adverse reactions. Therefore, their doctor needs to be aware.
- Blood type and Rhesus status
- Urinary culture
- High vaginal swab
- Cystic fibrosis (CFTR): this is an optional test that checks for all the known genetic mutations for cystic fibrosis.
Also, we recommend an ultrasound examination before the 12th week of gestation to ensure that the pregnancy is developing normally.
Weeks 12-14: Screening for chromosomal abnormalities
There are two basic examinations at 12-14 week of gestation that assess that the fetus is developing normally and exclude serious fetal defects.
- Ultrasound assessment of the nuchal translucency: this is an ultrasound examination that is performed by a doctor who specializes in fetal medicine. Nuchal translucency if the amount of fluid behind the fetal neck.
- Blood test to assess the levels of the protein PAPP-A and the hormone free β-hCG
What are the conditions that we are screening for?
The measurement of the nuchal translucency, combined with free β-hCG and PAPP-A estimate the risk of the fetus to have Down’s syndrome (Trisomy 21), Edward syndrome (Trisomy 18) or Patau syndrome (Trisomy 13), which are the most common chromosomal abnormalities. Increased nuchal translucency can also be associated with fetal cardiac defects, fetal anaemia, congenital infections, fetal hypo—proteinaemia, disturbances of fetal collagen production or of the lymphatic drainage. However, the majority of fetuses with increased nuchal translucency are normal. Nuchal translucency (NT) 3-4 mm is associated with 10% risk of fetal abnormality, NT of 4-5 mm with 30% risk, NT of 5-6.5 mm with 50% risk and finally NT of 6.5 mm with 85% risk of fetal abnormality. The detection rate for Down’s syndrome of nuchal translucency test alone is around 80% but with the addition of free β-hCG and PAPP-A it is near 90%.
What are the advantages of the method
Nuchal translucency test is a painless, non-invasive test that does not have side effects and is not associated with increased risk of miscarriage. However, it is a screening test. The only available diagnostic tests are the chorionic villus sampling (CVS) and the amniocentesis.
What are the alternatives?
Before 1990, amniocentesis was the only reliable method for diagnosis of Down’s syndrome. An arbitrary maternal age limit of 35 years old was set, above which amniocentesis was recommended. Nowadays, an invasive diagnostic test is recommended to women with risk for the fetus to have a chromosomal abnormality of more than 1/350, regardless of the maternal age. There are couples who wish to be certain that the fetus does not suffer from any chromosomal abnormality and are willing to take the 1% risk of miscarriage that is associated with an invasive diagnostic test (chorionic villus sampling or amniocentesis). On the other hand, some couples, for religious or other reasons, are against invasive testing that could risk miscarrying a healthy fetus. In conclusion, we respect each couple’s decision and treat the individual and not the numbers.
Are there any other markers for chromosomal abnormalities in the first trimester?
The presence or absence of the fetal nasal bone, the blood flow in the Ductus Venosus (a small vein in the fetal liver), the presence or absence of regurgitation in the tricuspid valve, the fetal heart rate, as well as other markers that are under research can increase the sensitivity of the test to 98%. If chromosomal and structural fetal abnormalities are excluded but there is increased nuchal translucency, testing for congenital infections (TORCH and Parvovirus B 19) is recommended.
We would recommend a test to assess the full blood count. Women who are Rhesus negative should have a test called “indirect Coombs’” that needs to be repeated monthly until delivery. This test shows if a sensitization event ever took place in case the fetus in Rhesus positive.
If the mother is Rhesus negative and the fetus Rhesus positive, we would advise for a maternal injection of anti-D antibodies (Rhophylac) at 32 weeks of gestation. This is in order to prevent maternal sensitization and production of antibodies that could affect a Rhesus positive fetus in a future pregnancy.
This is an invasive test for chromosomal abnormalities that is performed after 15 weeks of gestation. It is recommended if:
- The first trimester screening test for chromosomal abnormalities showed an increased risk for Down’s (trisomy 21), Edward (trisomy 18) or Patau (trisomy 13) syndrome
- A structural fetal abnormality was detected during the first trimester ultrasound that is associated with chromosomal abnormalities
- There is personal or family history that increases the risk for chromosomal abnormalities
In the past, amniocentesis was recommended to all women above the age of 35. Nowadays, age alone is not an absolute indication for amniocentesis. The doctor will assess if amniocentesis is indicated based on the risk for chromosomal abnormalities calculated after combining the nuchal translucency, the maternal age, the family and personal history etc.
In amniocentesis a needle is inserted through the maternal abdomen into the fetal amniotic cavity, under continuous ultrasound guidance. A small sample of the amniotic fluid that contains fetal cells and fetal genetic material is obtained and sent for testing. The results are available in the next few days.
The whole process is not painful but it can cause some discomfort. The risk of miscarriage after the procedure is 0.5-1%. Amniocentesis is a diagnostic test for fetal chromosomal abnormalities and is recommended when the benefits for the pregnancy outweigh the risk associated withthe procedure. The fetal sex can also be confirmed with amniocentesis.
- Abdominal ultrasound to assess the fetal well-being
- Transvaginal ultrasound to assess the cervical length. This is a highly recommended examination as cervical incompetence is one of the most common causes of premature labour. By checking the cervical length, the doctor assesses the risk for premature delivery and recommends if there is something that needs to be done for premature delivery to be avoided.
In addition to a fetal ultrasound examination there is a number of exams that need to be performed
- Full blood count
- Urinary culture
- Post-prandial blood sugar levels. This test is performed 1 hour after eating a toast and drinking one glass of juice. You should also repeat some tests that you have done in the first weeks of pregnancy (if you are not immune)
Weeks 21-23: fetal anomaly scan
This is a very important exam that is performed by a specialist in fetal medicine who checks the fetal anatomy.
The structures that are checked are:
- Fetal brain including measurement of lateral ventricles, assessment of the corpus callosum, assessment of the cerebellum and of the shape of the cranium
- Face and lips
- Neck and spine
- Kidneys, renal pelvises and fetal bladder
- Insertion of the umbilical cord in the fetal abdomen
- Umbilical cord
An abdominal ultrasound examination is performed in order to assess the fetal well-beingand a transvaginal examination that assesses the cervical length (see weeks 16-19).
In addition to the fetal ultrasound, the following tests need to be performed:
- Full blood count
- Screening for gestational diabetes
We also recommend Doppler test of the umbilical artery, in order to assess that the blood flow from the placenta to the fetus is normal and to exclude placental insufficiency. The Doppler examination is part of the fetal growth scan and not a separate test. Good placental function is associated with normal fetal growth. If there are indications of placental insufficiency, closer fetal monitoring is indicated.
In addition to the fetal ultrasound the following tests need to be performed:
- Full blood count
- Urinary culture
- Post-prandial blood sugar levels
You should also repeat some tests that you have done in the first weeks of pregnancy (if you are not immune)
We recommend fetal growth and Doppler scan (see weeks 28-30), in order to assess that the blood flow from the placenta to the fetus is normal. Doppler study is a special type of test that demonstrates the blood flow in a vessel.
After 32 weeks
From this stage onwards, the pregnancy is monitored more closely and childbirth classes are recommended. We also advise for a fetal growth scan, including Doppler examination (see weeks 28-30) every 2 weeks. Your midwife will also ask you to attend the childbirth classes that take place at the clinic. You are welcomed to attend with your partner. The purposes of the classes are to:
- Learn how to breath during labour
- Discuss about
- Symptoms of onset of labour
- What happens at the Delivery Suite
- Epidural anaesthesia
- Care of the neonate
- What you will need to bring for the neonate
- Share your experience with other women who are in the same position as you.
We will also answer any questions that you might have.
After 36 weeks
After 36 weeks of gestation we also recommend:
- Urinary dipstick: a quick examination of a urine sample that is performed at the clinic
- Fetal cardiotocography or non-stress test (NST)