Antenatal care for uncomplicated pregnancies
The frequent and systematic monitoring of your pregnancy by your obstetrician plays a key role in reducing the rates of maternal and perinatal morbidity and mortality. The appropriate advice and instructions regarding diet, exercise and lifestyle during pregnancy as well as the clinical, laboratory and ultrasound monitoring aim at the prevention and early detection of pregnancy complications.
During your first consultation with the obstetrician, it is recommended to confirm the diagnosis of a normal developing intrauterine pregnancy by performing an ultrasound examination between the 5th and 8th week of pregnancy. As soon as the diagnosis of gestational age is made and the detection of fetal cardiac activity is confirmed, the administration of folic acid supplements during the first trimester of pregnancy (recommended dose 400 mcg / day) should be recommended to prevent any potential neural tube defects. Detailed advice should also be given on the following topics:
- Hygiene and nutrition guidance, in order to reduce the risk of any maternal infections related to inappropriate food.
- Smoking cessation.
- Modification of medications harmful to the fetus, which were taken before pregnancy.
- Informing pregnant women about the negative effects of drug misuse and alcohol in pregnancy.
- Discussion about the importance of population screening tests during prenatal screening (screening for hemoglobinopathies, screening of fetal chromosomal abnormalities at the end of the first trimester and fetal anatomy scan during the second trimester).
- Sensitive topics, such as domestic violence, sexual abuse, psychological changes and drug misuse, should be addressed at every opportunity between the obstetrician and the pregnant woman, based on the particular relationship they develop during pregnancy.
- Scheduling pregnancy visits during pregnancy is also essential. In case of a first-born child with an uncomplicated or well-developed pregnancy, it is considered that 10 visits throughout the pregnancy are sufficient. In women who already have children, then a total of 7 antenatal visits for uncomplicated pregnancies are usually enough.
Ideally, the following laboratory tests should be suggested to pregnant women during the booking appointment:
1) General blood tests, blood group and Rhesus status. In Rhesus negative women, partner Rhesus should be checked as well as Coombs test in the maternal serum.
If anaemia is detected, iron on supplements should be recommended to the pregnant woman. Also, haemoglobin electrophoresis and sickle cell testing should be performed as early as possible during pregnancy, in order to detect carriers of hemoglobinopathies (thalassaemia, sickle cell disease). If the specific tests were performed in previous pregnancies, no repetition is required.
2) Urine dipstick and urine cultures should be performed early in pregnancy for early detection and treatment of asymptomatic bacteriuria that may otherwise lead to pyelonephritis and increased risk of preterm birth.
3) Biochemical test in early pregnancy for detection of hepatitis B, HIV and syphilis. In cases where the above tests are positive, then appropriate measures will be taken to prevent the vertical transmission of the infection from the mother to the fetus – newborn.
4) Rubella antibody test so that if it is found that women are not immuned, they should be protected from contact with high-risk groups (it is necessary to vaccinate it after childbirth in to achieve protection in future pregnancies).
5) The body mass index (BMI) should be calculated at the first antenatal visit in order to compare it with the body weight in the subsequent antenatal visits
6) The cervical smear test should not be done during pregnancy due to the hormonal changes that occur in the cells of the cervix which may subsequently affect the test and cause abnormal results. If the pregnant woman had the test scheduled and finds out she is pregnant, then the test should be performed three months after giving birth.
7) All pregnant women should have her blood pressure (BP) check in every antenatal visit and even more frequent BP checks could be suggested in cases where there are coexisting risk factors for preeclampsia (nulliparous, advanced maternal age, increased BMI, family history of pre-eclampsia, pre-existing hypertension or kidney disease, multiple pregnancy).
Antenatal visit at 11 – 13+6 weeks
At this stage of pregnancy, the progress of the pregnancy should be assessed discussion should take place on lifestyle and diet of the pregnant woman, as well as the pelvic floor exercises that can help during childbirth. Furthermore, the pregnant woman should be prepared about the maternity hospital in which she is going to deliver and become more familiar with the process of childbirth.
Ultrasound examination at this gestational age (first trimester ultrasound or nuchal translucency) must be performed in all pregnant women to detect chromosomal abnormalities of the fetus (trisomy 21, 18, 16). This detection is done with the combination of the following:
- History of the pregnant woman (pregnant age, gestational age)
- Ultrasound findings (nuchal translucency, presence / absence of nasal bone etc)
- Blood test: measurement of β-chorionic gonadotropin and pregnancy-related protein A (PAPP-A)
Based on the above, the final recombinant probability for Down syndrome and the remaining trisomies is calculated. In the event of an indicative high risk for fetal trisomy, you should seek appropriate advice from an Obstetrician with special interest in Fetal Medicine to discuss further diagnostic tests, such as chorionic villus sampling (CVS) or amniocentesis.
If the pregnant woman misses or does not undergo the first trimester scan for any reason, then she should follow the ‘triple test’, between 15 – 20 weeks of gestation; this involves the measurement of β-chorionic gonadotropin in combination with estriol and -fetoprotein, which provide useful information about the possible risk of fetal trisomy.
The evaluation of the laboratory tests requested by the pregnant woman at the first antenatal visit could be discussed. Finally, the anatomy scan of the fetus during the second trimester does not replace the nuchal translucency scan in terms of its value in population screening for chromosomal abnormalities.
Antenatal visit at 16 – 17+6 weeks
During this visit, you should be examined clinically have your weight and blood pressure checked and the fetal heart rate should be auscultated. Repeat urine dipstick and urine culture should be sent if indicated by the urine dipstick or presence of urinary symptoms.
Antenatal visit between 20 – 23+6 weeks
The fetal anatomy scan must be performed by all pregnant women in order to detect fetal abnormalities, and subsequently provide appropriate counselling to the couple so they could make timely decisions (intrauterine treatment of the fetus, termination of pregnancy, supportive care, planned childbirth in a tertiary neonatal unit for the subsequent treatment of the newborn). At the same time during this visit, blood pressure, body weight and urine tests should be performed.
Antenatal visit at 28 weeks
During this visit you should have the routine clinical examination, blood pressure check and urine dipstick. Rhesus-negative pregnant women are tested for antibodies and according to the results, anti-D injection is administered.
Pregnant women with risk factors for gestational diabetes mellitus (GDM) are advised to undergo appropriate glucose tolerance test (fasting glucose measurement of fasting glucose, as well as following administration of 75 g of glucose at 60 and 120 minutes). The risk factors for GDM are the following:
- Body mass index over 30 kg / m2
- Personal history of previous childbirth of a baby weighing more than 4.5 kg
- Personal history of GDM in previous pregnancy
- Family history of type 1 or type 2 diabetes.
Systematic ultrasound examination to determine the development of the fetus or to assess the length of the cervix and the risk of preterm labour is not recommended after 24 weeks of pregnancy. Only in cases of low lying placenta or placenta praevia during the second trimester ultrasound scan should have a repeat abdominal scan.
Antenatal visits at 32, 34, 36, 38, 40 weeks
Regular check of body weight, blood pressure and urine dipstick should be performed at each visit. A systemic Doppler ultrasound examination of an umbilical artery is not recommended for the prognosis of intrauterine fetal growth restriction in healthy pregnant women with low-risk pregnancies.
Obviously, if the mother refuses to have induction of labour during the 41st week of pregnancy, fetal wellbeing should be ensured in the period leading up to childbirth, with at least an ultrasound scan and cardiotocograph (CTG) twice a week.
Dr Efterpi Tingi
Consultant Obstetrician and Gynaecologist
