1 Antenatal care
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- Goals of good antenatal care
- Diagnosing pregnancy
- The first antenatal visit
- Determining the duration of pregnancy
- Side-room and special screening investigations
- The second antenatal visit
- Assessing the results of the special screening investigations
- Grading the risk
- Subsequent visits
- The visit at 28 weeks
- The visit at 34 weeks
- The visit at 41 weeks
- Managing women with HIV infection
- Case studies
When you have completed this unit you should be able to:
- List the goals of good antenatal care.
- Diagnose pregnancy.
- Know what history should be taken and examination done at the first visit.
- Determine the duration of pregnancy.
- List and assess the results of the side-room and screening tests needed at the first visit.
- Identify low-, intermediate- and high-risk pregnancies.
- Plan and provide antenatal care that is problem orientated.
- List what specific complications to look for at 28, 34 and 41 weeks.
- Provide health information during antenatal visits.
- Manage pregnant women with HIV infection.
Goals of good antenatal care
1-1 What are the aims and principles of good antenatal care?
The aims of good antenatal care are to ensure that pregnancy causes no harm to the mother and to keep the fetus healthy during the antenatal period. In addition, the opportunity must be taken to provide health education. These aims can usually be achieved by the following:
- Antenatal care must follow a definite plan.
- Antenatal care must be problem oriented.
- Identify risk factors from the previous obstetric history.
- Possible complications and risk factors that may occur at a particular gestational age must be looked for at these visits.
- The fetal condition must be repeatedly assessed.
- Healthcare education must be provided.
All information relating to the pregnancy must be entered in a patient-held Maternity Case Record. The Maternity Case Record can also serve as a referral letter if a patient is referred to the next level of care and therefore serves as a link between the different levels of care as well as the antenatal clinic and labour ward.
The antenatal card is an important source of information during the antenatal period and labour.
Figure 1-1: The front of an antenatal record card
Figure 1-2: The back of an antenatal record card
1-2 How can you confirm that a patient is pregnant?
The common symptoms of pregnancy are amenorrhoea (no menstruation), nausea, breast tenderness and urinary frequency. If the history suggests that a patient is pregnant, the diagnosis is easily confirmed by testing the urine with a standard pregnancy test. The test becomes positive by the time the first menstrual period is missed.
A positive pregnancy test is produced by both an intra-uterine and an extra-uterine pregnancy. Therefore, it is important to establish whether the pregnancy is intra-uterine or not.
Confirm that the patient is pregnant before beginning antenatal care.
1-3 How do you diagnose an intra-uterine pregnancy?
The characteristics of an intra-uterine pregnancy are:
- The size of the uterus is appropriate for the duration of pregnancy.
- There is no lower abdominal pain or vaginal bleeding.
- There is no tenderness of the lower abdomen.
1-4 How do you diagnose an extra-uterine pregnancy?
The characteristics of an extra-uterine (ectopic) pregnancy are:
- The uterus is smaller than expected for the duration of pregnancy.
- Lower abdominal pain and vaginal bleeding are usually present.
- Tenderness over the lower abdomen is usually present.
The first antenatal visit
This visit is usually the patient’s first contact with medical services during her pregnancy. She must be treated with kindness and understanding in order to gain her confidence and to ensure her future co-operation and regular attendance. This opportunity must be taken to book the patient for antenatal care and thereby ensure the early detection and management of treatable complications.
1-5 At what gestational age (duration of pregnancy) should a patient first attend an antenatal clinic?
As early as possible, preferably when the second menstrual period has been missed, i.e. at a gestational age of 8 weeks. Note that for practical reasons the gestational age is measured from the first day of the last normal menstrual period. Antenatal care should start at the time that the pregnancy is confirmed.
It is important that all pregnant women book for antenatal care as early as possible.
1-6 What are the aims of the first antenatal visit?
- A full history must be taken.
- A full physical examination must be done.
- The duration of pregnancy must be established.
- Important screening tests must be done.
- Some high-risk patients can be identified.
1-7 What history should be taken?
A full history, containing the following:
- The previous obstetric history.
- The present obstetric history.
- A medical history.
- HIV status.
- History of medication and allergies.
- A surgical history.
- A family history.
- The social circumstances of the patient.
1-8 What is important in the previous obstetric history?
- Establish the number of pregnancies (gravidity), the number of previous pregnancies reaching viability (parity) and the number of miscarriages and ectopic pregnancies that the patient may have had. This information may reveal the following important factors:
- Grande multiparity (i.e. five or more pregnancies which have reached viability).
- Miscarriages: 3 or more successive first-trimester miscarriages suggest a possible genetic abnormality in the father or mother. A previous midtrimester miscarriage suggests a possible incompetent internal cervical os.
- Ectopic pregnancy: ensure that the present pregnancy is intra-uterine.
- Multiple pregnancy: non-identical twins tend to recur.
- The birth weight, gestational age, and method of delivery of each previous infant as well as of previous perinatal deaths are important.
- Previous low-birth-weight infants or spontaneous preterm labours tend to recur.
- Previous large infants (4 kg or more) suggest maternal diabetes.
- The type of previous delivery is also important: a forceps delivery or vacuum extraction may suggest that a degree of cephalopelvic disproportion had been present. If the patient had a previous Caesarean section, the indication for the Caesarean section must be determined.
- The type of incision in the uterus is also important (this information must be obtained from the patient’s folder) as only patients with a transverse lower segment incision should be considered for a possible vaginal delivery.
- Having had one or more perinatal deaths places the patient at high risk of further perinatal deaths. Therefore, every effort must be made to find out the cause of any previous deaths. If no cause can be found, then the risk of a recurrence of perinatal death is even higher.
- Previous complications of pregnancy or labour.
- In the antenatal period, e.g. pre-eclampsia, preterm labour, diabetes, and antepartum haemorrhage. Patients who develop pre-eclampsia before 34 weeks gestation have a greater risk of pre-eclampsia in further pregnancies.
- First stage of labour, e.g. a long labour.
- Second stage of labour, e.g. impacted shoulders.
- Third stage of labour, e.g. a retained placenta or a postpartum haemorrhage.
Complications in previous pregnancies tend to recur in subsequent pregnancies. Therefore, patients with a previous perinatal death are at high risk of another perinatal death, while patients with a previous spontaneous preterm labour are at high risk of preterm labour in their next pregnancy.
1-9 What information should be asked for when taking the present obstetric history?
- The first day of the last normal menstrual period must be determined as accurately as possible.
- Any medical or obstetric problems which the patient has had since the start of this pregnancy, for example:
- Pyrexial illnesses (such as influenza) with or without skin rashes.
- Symptoms of a urinary tract infection.
- Any vaginal bleeding.
- Attention must be given to minor symptoms which the patient may experience during her present pregnancy, for example:
- Nausea and vomiting.
- Oedema of the ankles and hands.
- Is the pregnancy planned and wanted, and was there a period of infertility before she became pregnant?
- If the patient is already in the third trimester of her pregnancy, attention must be given to the condition of the fetus.
1-10 What important facts must be considered when determining the date of the last menstrual period?
- The date should be used to measure the duration of the pregnancy only if the patient had a regular menstrual cycle.
- Were the date of onset and the duration of the last period normal? If the last period was shorter in duration and earlier in onset than usual, it may have been an implantation bleed. Then the previous period must be used to determine the duration of pregnancy.
- Patients on oral, injectable or subdermal contraception must have menstruated spontaneously after stopping contraception, otherwise the date of the last period should not be used to measure the duration of pregnancy.
1-11 Why is the medical history important?
Some medical conditions may become worse during pregnancy, e.g. a patient with heart valve disease may go into cardiac failure while a hypertensive patient is at high risk of developing pre-eclampsia.
Ask the patient if she has had any of the following:
- Diabetes mellitus.
- Rheumatic or other heart disease.
- Psychiatric illness.
- Any other major illness.
It is important to ask whether the patient knows her HIV status. If she had an HIV test, both the date and result need to be noted. If she is HIV positive, record whether she is on ARV treatment and which drugs she is taking. If she is not on ARV treatment, note whether she knows her CD4 count as well as viral load and when it was done.
1-12 Why is it important to ask about any medication taken and a history of allergy?
- Ask about the regular use of any medication. This is often a pointer to an illness not mentioned in the medical history.
- Certain drugs, such as retinoids which are used for acne, and efavirenz (Stocrin) which is used in ARV treatment, can be teratogenic (damaging to the fetus) during the first trimester of pregnancy.
- Some drugs, such as Warfarin, can be dangerous to the fetus if they are taken close to term.
- Allergies are also important and the patient must be specifically asked if she is allergic to penicillin.
1-13 What previous operations may be important?
- Operations on the urogenital tract, e.g. Caesarean section, myomectomy, a cone biopsy of the cervix, operations for stress incontinence, and vesicovaginal fistula repair.
- Cardiac surgery, e.g. heart valve replacement.
1-14 Why is the family history important?
Close family members with a condition such as diabetes, multiple pregnancy, bleeding tendencies or mental retardation increases the risk of these conditions in the patient and her unborn infant. Some birth defects are inherited.
1-15 Why is information about the patient’s social circumstances very important?
- Ask if the woman smokes cigarettes or drinks alcohol. Smoking may cause intra-uterine growth restriction (fetal growth restriction) while alcohol may cause both intra-uterine growth restriction and congenital malformations.
- A mother not in a stable relationship with the father of her baby may need help to plan for the care of her infant.
- Unemployment, poor housing, and overcrowding increase the risk of tuberculosis, malnutrition, and intra-uterine growth restriction. Patients living in poor social conditions need special support and help.
1-16 To which systems must you pay particular attention when doing a physical examination?
- The general appearance of the patient is of great importance as it can indicate whether or not she is in good health.
- A woman’s height and weight may reflect her past and present nutritional status.
- In addition, the following systems or organs must be carefully examined:
- The thyroid gland.
- The breasts.
- Lymph nodes in the neck, axillae (armpits) and inguinal areas.
- The respiratory system.
- The cardiovascular system.
- The abdomen.
- Both external and internal genitalia.
1-17 What is important in the examination of the thyroid gland?
- A thyroid gland which is visibly enlarged is possibly abnormal and must be examined by a doctor.
- A thyroid gland which on palpation is only slightly diffusely enlarged is normal in pregnancy.
- An obviously enlarged gland, a single palpable nodule, or a nodular goitre is abnormal and needs further investigation.
1-18 What is important in the examination of the breasts?
- Inverted or flat nipples must be diagnosed and treated so that the patient will be more likely to breastfeed successfully.
- A breast lump or a blood-stained discharge from the nipple must be investigated further as it may indicate the presence of a tumour.
- Whenever possible, patients should be advised and encouraged to breastfeed. Teaching the advantages of breastfeeding is an essential part of antenatal care and must be emphasised in the following groups of women:
- HIV-negative women.
- Women with unknown HIV status.
- HIV-positive women who have elected to exclusively breastfeed.
1-19 What is important in the examination of the respiratory and cardiovascular systems?
- Look for any signs which suggest that the patient has difficulty breathing (dyspnoea).
- The blood pressure must be measured and the pulse rate counted.
1-20 How do you examine the abdomen at the booking visit?
- The abdomen is palpated (felt) for enlarged organs or masses.
- The height of the fundus above the symphysis pubis is measured.
1-21 What must be looked for when the external and internal genitalia are examined?
- Signs of sexually transmitted diseases which may present as single or multiple ulcers, a purulent discharge or enlarged inguinal lymph nodes.
- Carcinoma of the cervix is the commonest form of cancer in most communities. Advanced stages of this disease present as a wart-like growth or an ulcer on the cervix. A cervix which looks normal does not exclude the possibility of an early cervical carcinoma.
1-22 When must a cervical smear be taken when examining the internal genitalia (gynaecological examination)?
- All patients aged 30 years or more who have not previously had a cervical smear that was reported as normal.
- All patients who have previously had a cervical smear that was reported as abnormal.
- All patients who have a cervix that looks abnormal.
- All HIV-positive patients who did not have a cervical smear reported as normal within the last year.
A cervix that looks normal may have an early carcinoma.
Determining the duration of pregnancy
All available information is now used to assess the duration of pregnancy as accurately as possible:
- Last normal menstrual period.
- Size of the uterus on bimanual or abdominal examination up to 18 weeks.
- Height of the fundus at or after 18 weeks.
- The result of an ultrasound examination (ultrasonology).
An accurate assessment of the duration of pregnancy is of great importance, especially if the woman develops complications later in her pregnancy.
1-23 When is the duration of pregnancy calculated from the last normal menstrual period?
When there is certainty about the accuracy of the dates of the last normal menstrual period. The duration of pregnancy is then calculated from the first day of that period.
1-24 How does the size of the uterus indicate the duration of pregnancy?
- Up to 12 weeks the size of the uterus, assessed by bimanual examination, is a reasonably accurate method of determining the duration of pregnancy. Therefore, if there is uncertainty about the duration of pregnancy before 12 weeks the patient should be referred for a bimanual examination.
- From 13 to 17 weeks, when the fundus of the uterus is still below the umbilicus, the abdominal examination is the most accurate method of determining the duration of pregnancy.
- From 18 weeks, the symphysis-fundus (SF) height measurement is the more accurate method.
1-25 How should you determine the duration of pregnancy if the uterine size and the menstrual dates do not indicate the same gestational age?
- If the fundus is below the umbilicus (in other words, the patient is less than 22 weeks pregnant).
- If the dates and the uterine size differ by more than 3 weeks, the uterine size should be considered as the more accurate indicator of the duration of pregnancy.
- If the dates and the uterine size differ by 3 weeks or less, the dates are more likely to be correct.
- If the fundus is at or above the umbilicus (in other words, the patient is 22 weeks or more pregnant).
- If the dates and the uterine size differ by more than 4 weeks, the uterine size should be considered as the more accurate indicator of the duration of pregnancy.
- If the dates and the uterine size differ by 4 weeks or less, the dates are more likely to be correct.
1-26 How should you use the symphysis-fundus height measurement to determine the duration of pregnancy?
From 18 weeks gestation, the symphysis-fundus (SF) height measurement in cm is plotted on the 50th centile of the SF growth curve to determine the duration of pregnancy. For example, a SF measurement of 26 cm corresponds to a gestation of 27 weeks.
A difference between the gestational age according to the menstrual dates and the size of the uterus is usually the result of incorrect dates.
1-27 What conditions other than incorrect menstrual dates cause a difference between the duration of pregnancy calculated from menstrual dates and the size of the uterus?
- A uterus bigger than dates suggests:
- Multiple pregnancy.
- A fetus which is large for the gestational age.
- Diabetes mellitus.
- A uterus smaller than dates suggests:
- Intra-uterine growth restriction.
- Intra-uterine death.
- Rupture of the membranes.
Side-room and special screening investigations
1-28 Which side-room examinations must be done routinely?
- A haemoglobin estimation at the first antenatal visit and again at 28 and 36 weeks.
- A urine test for protein and glucose is done at every visit.
1-29 What special screening investigations should be done routinely?
- A serological screening test for syphilis. An on-site syphilis rapid test can be performed in the clinic, if a laboratory is not within easy reach of the hospital or clinic.
- Determining whether the patient’s blood group is Rh positive or negative. A Rh card test can be done in the clinic.
- A rapid HIV screening test after health worker initiated counselling and preferably after written consent.
- A smear of the cervix for cytology if it is indicated.
- If possible, all patients should have a midstream urine specimen sent for culture to diagnose asymptomatic bacteriuria.
- Where possible, an ultrasound examination when the patient is 18–22 weeks pregnant can be arranged
- Ultrasound screening at 11 to 13 weeks for nuchal thickness, or the triple test, is very useful in screening for Down syndrome and other chromosomal abnormalities.
1-30 Is it necessary to do an ultrasound examination on all patients who book early enough for antenatal care?
With well-trained ultrasonographers and adequate ultrasound equipment, it is of great value to:
- Accurately determine the gestational age if the first ultrasound examination is done at 24 weeks or less. With uncertain gestational age the fundal height will measure less than 24 cm.
- Diagnose multiple pregnancies early.
- Identify the site of the placenta.
- Diagnose severe congenital abnormalities.
If it is not possible to provide ultrasound examinations to all antenatal patients before 24 weeks gestation, the following groups of patients may benefit greatly from the additional information which may be obtained:
- Patients with a gestational age of 14 to 16 weeks:
- Patients aged 37 years or more because of their increased risk of having a fetus with a chromosomal abnormality (especially Down syndrome). A patient who would agree to termination of pregnancy if the fetus was abnormal, should be referred for amniocentesis.
- Patients with a previous history or family history of congenital abnormalities. The nearest hospital with a genetic service should be contacted to determine the need for amniocentesis.
- Patients with a gestational age of 18 to 22 weeks:
- Patients needing elective delivery (e.g. those with two previous Caesarean sections, a previous perinatal death, a previous vertical uterine incision or hysterotomy, and diabetes).
- Gross obesity when it is often difficult to determine the duration of pregnancy.
- Previous severe pre-eclampsia or preterm labour before 34 weeks. As there is a high risk of recurrence of either complication, accurate determination of the duration of pregnancy greatly helps in the management of these patients.
- Rhesus sensitisation where accurate determination of the duration of pregnancy helps in the management of the patient.
- Where the capacity exists ultrasound examination can be done for gestational age determination up to a fundal height measurement of 30 cm and for all patients with a body mass index of 40 or more (morbidly obese) as the fundal height is unreliable in these patients.
1-31 What is the assessment of risk after booking the patient?
Once the patient has been booked for antenatal care, it must be assessed whether she or her fetus have complications or risk factors present, as this will decide when she should be seen again. At the first visit some patients could already be placed in a high-risk category.
1-32 If no risk factors are found at the booking visit, when should the patient be seen again?
She should be seen again when the results of the special investigations requested at the first visit are available, preferably 1 to 2 weeks after the booking visit. However, if no risk factors were noted and the screening tests were normal the second visit is omitted.
1-33 If there are risk factors noted at the booking visit, when should the patient be seen again?
- A patient with an underlying illness must be admitted for further investigation and treatment.
- A patient with a risk factor is followed up sooner if necessary:
- The management of a patient with chronic hypertension would be planned and the patient would be seen a week later.
- A newly diagnosed HIV-positive patient must be seen a week later to obtain her serum creatinine and CD4 count results.
1-34 How should you list risk factors?
All risk factors must be entered on the problem list on the back of the antenatal card. The gestational age when management is needed should be entered opposite the gestational age at the top of the card, e.g. vaginal examination must be done at each visit from 26 to 32 weeks if there is a risk of preterm labour.
The clinic checklist (Figure 1-3) for the first visit could now be completed. If all the open blocks for the first visit can be ticked off, the visit is completed and all important points have been addressed. The follow-up visit checklist (Figure 1-4) should again be used during further visits to make sure that all problems have been considered (i.e. it should be used as a quality control tool).
Figure 1-3: The front of a clinic checklist
Figure 1-4: The back of a clinic checklist
The second antenatal visit
1-35 What are the aims of the second antenatal visit?
If the results of the screening tests were not available by the end of the first antenatal visit, or special investigations were requested, a second visit should be arranged 2 weeks later. The aims of this second visit are:
- To review and act on the results of the screening or special investigations done at the booking visit.
- To perform the second assessment for risk factors.
If possible, all the results of the screening tests should be obtained at the first visit.
Assessing the results of the special screening investigations
1-36 How should you interpret the results of the VDRL or RPR screening tests for syphilis?
The correct interpretation of the results is of the greatest importance:
- If either the VDRL (Venereal Disease Research Laboratory), or RPR (Rapid Plasmin Reagin )testis negative, then the patient does not have syphilis and no further tests for syphilis are needed.
- If the VDRL or RPR titre is 1:16 or higher, the patient has syphilis and must be treated.
- If the VDRL or RPR titre is 1:8 or lower (or the titre is not known), the laboratory should test the same blood sample by means of the TPHA (Treponema Pallidum Haemagglutin Assay) or FTA (Fluorescent Treponemal Antibody) test:
- If the TPHA or FTA is also positive, the patient has syphilis and must be fully treated.
- If the TPHA or FTA is negative, then the patient does not have syphilis and, therefore, need not be treated.
- If a TPHA or FTA test cannot be done, and the patient has not been fully treated for syphilis in the past 3 months, she must be given a full course of treatment.
A syphilis rapid test can be done instead of a TPHA or FTA test.
A VDRL or RPR titre of less than 1 in 16 may be caused by syphilis.
- The syphilis rapid test or VDRL and RPR tests may still be negative during the first few weeks after infection with syphilis as the patient has not yet had enough time to form antibodies. The VDRL and RPR tests detect regain antibodies which indicate present syphilis infection while the TPHA, FTA and syphilis rapid tests detect spirichaetal antibodies which indicate syphilis at any time in that person’s life. VDRL and RPR titres of less than 1:16 may be present with recent infection or recent treatment as well as with latent syphilis. Full treatment is given unless the patient and her partner have been fully treated in the past 3 months.
1-37 How should the results of the syphilis rapid test be interpreted?
- If the test is negative the patient does not have syphilis.
- If the test is positive the person either has active (untreated) syphilis or was infected in the past and no longer has active disease. The diagnosis of active syphilis must be confirmed or rejected by a VDRL or RPR test. It is advisable that treatment for syphilis be started immediately while waiting for the result of the RPR or VDRL test. If the laboratory test is negative treatment can be stopped as it is an old infection that was fully treated. If the test is positive, irrespective of the titre, the full treatment course must be completed.
1-38 What is the treatment of syphilis in pregnancy?
The treatment of choice is penicillin. If the patient is not allergic to penicillin, she is given benzathine penicillin (Bicillin LA or Penilente LA) 2.4 million units intramuscularly weekly for 3 weeks. At each visit 1.2 million units is given into each buttock. This is a painful injection so the importance of completing the full course must be impressed on the patient.
Benzathine penicillin crosses the placenta and also treats the fetus.
If the patient is allergic to penicillin, she is given erythromycin 500 mg 6-hourly orally for 14 days. This may not treat the fetus adequately, however. Tetracycline is contraindicated in pregnancy as it may damage the fetus.
1-39 How should the results of the rapid HIV test be interpreted?
- If the rapid HIV test is negative, there is a very small chance that the patient is HIV positive. The patient should be informed about the result and given counselling to help her to maintain her negative status.
- If the rapid HIV test is positive, a second rapid test should be done with a kit from another manufacturer. If the second test is also positive, then the patient is HIV positive. The patient should be given the result, and post-test counselling for an HIV-positive patient should be provided. Commence the patient on FDC if there are no contra-indications.
- If the first rapid test is positive and the second negative, the patient’s HIV status is uncertain. This information should be given to the patient and blood should be taken and sent to the nearest laboratory for an ELISA test for HIV.
- If the ELISA test is negative, there is only a very small chance that the patient is HIV positive.
- If the ELISA test is positive, the patient is HIV positive.
1-40 What should you do if the cervical cytology result is abnormal?
- A patient whose smear shows an infiltrating cervical carcinoma must immediately be referred to the nearest gynaecological oncology clinic (level 3 hospital). The duration of pregnancy is very important, and this information (determined as accurately as possible) must be available when the unit is phoned.
- A patient with a smear showing a low grade CIL (cervical intra-epithelial lesion) such as CIN I (cervical intra-epithelial neoplasia), atypia or only condylomatous changes is checked after 9 months, or as recommended on the cytology report.
- A patient with a smear showing a high grade CIL, such as CIN II or III or atypical condylomatous changes, must get an appointment at the nearest gynaecology or cytology clinic.
- Abnormal vaginal flora is only treated if the patient is symptomatic.
- A colposcopy will be done at the referral clinic. If there are no signs of infiltrating cervical carcinoma, the patient can deliver normally and receive further treatment six weeks after birth. A patient with a macroscopically normal cervix, who comes from an area which does not have access to a gynaecological or colposcopy clinic, must have her smear repeated at 32 weeks gestation. If the result is unchanged, the patient may deliver normally and receive further treatment six weeks after delivery. Biopsies must be taken from areas which are macroscopically suspicious of cervical carcinoma to exclude infiltrating carcinoma.
- The latest information from the Cochrane Library indicates that treating bacterial vaginosis does not reduce the risk of preterm labour.
It is essential to record on the antenatal card the plan that has been decided upon, and to ensure that the patient is fully treated after delivery.
1-41 What should you do if the patient’s blood group is Rh negative?
Between 5 and 15% of patients are Rhesus negative (i.e. they do not have the Rhesus D antigen on their red cells). The blood grouping laboratory will look for Rhesus anti-D antibodies in these patients. If the Rh card test was used, blood must be sent to the blood grouping laboratory to confirm the result and look for Rhesus anti-D antibodies.
- If there are no anti-D antibodies present, the patient is not sensitised. Blood must be taken at 26, 32 and 38 weeks of pregnancy to determine if the patient has developed anti-D antibodies since the first test was done.
- If anti-D antibodies are present, the patient has been sensitised to the Rhesus D antigen. With an anti-D antibody titre of 1:16 or higher, she must be referred to a centre which specialises in the management of this problem. If the titre is less than 1:16, the titre should be repeated within 2 weeks or as directed by the laboratory.
1-42 What is the importance of atypical antibodies?
The presence of these antibodies indicates that the patient has been sensitised to a red-cell antigen other than the Rhesus D antigen. The husband’s blood must be examined to determine if he has the antigen which gave rise to the development of these maternal antibodies.
- If this is the case, then these atypical antibodies may endanger the fetus, and the laboratory or referral hospital must be consulted as to the further management of the patient.
- If not, then the atypical antibodies are usually the result of an incompatible blood transfusion which the patient has had, and they will not endanger the fetus.
1-43 What should you do if the ultrasound findings do not agree with the patient’s dates?
Between 18 and 22 weeks:
- If the duration of pregnancy, as suggested by the patient’s menstrual dates, falls within the range of the duration of pregnancy as given by the ultrasonographer (usually 3 to 4 weeks), the dates should be accepted as correct.
- However, if the dates fall outside the range of the ultrasound assessment, then the dates must be regarded as incorrect.
If the ultrasound examination is done in the first trimester (14 weeks or less), the error in determining the gestational age is only 1 week (range 2 weeks).
If the ultrasound examination is done in the second trimester the error is 2 weeks (range 4 weeks).
1-44 What action should you take if an ultrasound examination at 18 to 22 weeks shows a placenta praevia?
In most cases the placenta will move out of the lower segment as pregnancy progresses, as the size of the uterus increases more than the size of the placenta. Therefore, a follow-up ultrasound examination must be arranged at 32 weeks, where a placenta praevia type II or higher has been diagnosed, to assess whether the placenta is still praevia.
1-45 What should you do if the ultrasound examination shows a possible fetal abnormality?
The patient must be referred to a level 3 hospital for detailed ultrasound evaluation and a decision about further management.
Grading the risk
Once the results of the special investigations have been obtained, all patients must be graded into a risk category. (A list of risk factors and the level of care needed is given in appendix 1). A few high-risk patients would have already been identified at the first antenatal visit while others will be identified at the second visit.
1-46 What are the risk categories?
There are three risk categories:
- Low (average) risk
- Intermediate risk
- High risk
A low-risk patient has no maternal or fetal risk factors present. These patients can receive primary care from a midwife.
An intermediate-risk patient has a problem which requires some, but not continuous, additional care. For example, a grande multipara should be assessed at her first or second visit for medical disorders, and at 34 weeks for an abnormal lie. She also requires additional care during labour and postpartum. She, therefore, is at an increased risk of problems only during part of her pregnancy, labour and puerperium. Most of the antenatal care in these patients can be given by a midwife.
A high-risk patient has a problem which requires continuous additional care. For example, a patient with heart valve disease or a patient with a multiple pregnancy. These patients usually require care by a doctor.
- The subsequent visits must be problem oriented.
- The visits at 28, 34 and 41 weeks are more important visits. At these visits, complications specifically associated with the duration of pregnancy are looked for.
- From 28 weeks onwards the fetus is viable and the fetal condition must, therefore, be regularly assessed.
1-47 When should a patient return for further antenatal visits?
If a patient books in the first trimester, and is found to be at low risk, her subsequent visits can be arranged as follows:
- Every 8 weeks until 28 weeks.
- The next visit is six weeks later at 34 weeks.
- Primigravidas are then seen every 2 weeks from 36 weeks and multigravidas from 38 weeks. However, multigravidas are also seen again at 36 weeks if a breech presentation was found at their 34 week visit.
- Thereafter primigravidas are seen at 40 weeks and 41 weeks while multigravidas are only seen at 41 weeks, if they have not yet delivered.
In some rural areas it may be necessary to see low-risk patients less often because of the large distances involved. The risk of complications with less frequent visits in these patients is minimal. Visits may be scheduled as follows: after the first visit (combining the booking and second visit), the follow-up visits at 28, 34 and 41 weeks.
1-48 Which patients should have more frequent antenatal visits?
If a complication develops, the risk grading will change. This change must be clearly recorded on the patient’s antenatal card. Subsequent visits will now be more frequent, depending on the nature of the risk factor.
Primigravidas, whenever possible, must be seen every 2 weeks from 36 weeks, even if it is only to check the blood pressure and test the urine for protein, because they are a high-risk group for developing pre-eclampsia.
A waiting area (obstetric village), where cheap accommodation is available for patients, provides an ideal solution for some intermediate-risk patients, high-risk patients and the above-mentioned primigravidas, so that they can be seen more regularly.
The visit at 28 weeks
1-49 What important complications of pregnancy should be looked for?
- Antepartum haemorrhage becomes a very important high-risk factor from 28 weeks.
- Early signs of pre-eclampsia may now be present for the first time, as it is a problem which develops in the second half of pregnancy. Therefore, the patient must be assessed for proteinuria and a rise in the blood pressure.
- Cervical changes in a patient who is at high risk for preterm labour, e.g. a patient with multiple pregnancy, a history of previous preterm labour, or polyhydramnios.
- If the symphysis-fundus height measurement is below the 10th centile, assess the patient for causes of poor fundal growth.
- If the symphysis-fundus height measurement is above the 90th centile, assess the patient for the causes of a uterus larger than dates.
- Anaemia may be detected for the first time during pregnancy.
- Diabetes in pregnancy may present now with glycosuria. If so, a random blood glucose concentration must be measured.
1-50 Why is an antepartum haemorrhage a serious sign?
- Abruptio placentae causes many perinatal deaths.
- It may also be a warning sign of placenta praevia.
1-51 How should you monitor the fetal condition?
- All women should be asked about the frequency of fetal movements and informed that they must report immediately if the movements suddenly decrease or stop.
- If a patient has possible intra-uterine growth restriction or a history of a previous fetal death, then she should count fetal movements once a day from 28 weeks and record them on a fetal-movement chart.
The visit at 34 weeks
1-52 Why is the 34 weeks visit important?
- All the risk factors of importance at 28 weeks (except for preterm labour) are still important and must be excluded.
- The lie of the fetus is now very important and must be determined. If the presenting part is not cephalic, then an external cephalic version must be attempted at 36 weeks if there are no contraindications. A grande multipara who goes into labour with an abnormal lie is at high risk of rupturing her uterus.
- Patients who have had a previous Caesarean section must be assessed with a view to the safest method of delivery. A patient with a small pelvis, a previous classical Caesarean section, as well as other recurrent causes for a Caesarean section must be booked for an elective Caesarean section at 39 weeks.
- The patient’s breasts must be examined again for flat or inverted nipples, or eczema of the areolae which may impair breastfeeding. Eczema should be treated.
- If the first HIV screen was negative, it should be repeated around 32 weeks gestation to detect any late infections.
The visit at 41 weeks
1-53 Why is the visit at 41 weeks important?
A patient whose pregnancy extends beyond 42 weeks has an increased risk of developing the following complications:
- Intrapartum fetal distress.
- Meconium aspiration.
- Intra-uterine death.
1-54 How should you manage a patient who is 41 weeks pregnant?
- A patient with a complication such as intra-uterine growth restriction (retardation) or pre-eclampsia must have labour induced.
- A patient who booked early and was sure of her last menstrual period and where, at the booking visit, the size of the uterus corresponded to the duration of pregnancy by dates must have the labour induced on the day she reaches 42 weeks. The same applies to a patient whose duration of pregnancy was confirmed by ultrasound examination before 24 weeks.
- A patient who is unsure of her dates, or who booked late, must have an ultrasound examination on the day she reaches 42 weeks to determine the amount of amniotic fluid present.
- If the amniotic fluid index (AFI) is 5 or more (or if the largest pool of liquor measures 3 cm or more) and the patient reports good fetal movement, she should be reassessed in 1 week’s time.
- If the AFI is less than 5 (or if the largest pool of liquor measures less than 3 cm), labour must be induced.
- The amniotic fluid index measures the largest vertical pool of liquor in the each of the 4 quadrants of the uterus and adds them together.
Remember that the commonest cause of being post-term is wrong dates.
- If the patient is to be induced, a surgical induction of labour may be performed if the cervix is favourable and the patient is HIV negative. With an unfavourable cervix or HIV-positive patient, provide a medical induction of labour with misoprostol (Cytotec) 50 µg (a quarter of a tablet) every 4 hours orally until a total of 4 doses (total = 200 µg). Prostaglandin E2 (Prepidil gel 0.5 mg or Prandin 1 mg) can also be used. Induction of labour should take place in a hospital with facilities for Caesarean section.
It is very important that the above problems are actively looked for at 28, 34 and 41 weeks. It is best to memorise these problems and check then one by one at each visit.
1-55 How should the history, clinical findings and results of the special investigations be recorded in low-risk patients?
There are many advantages to a hand-held Maternity Case Record that includes an antenatal card which records all the patient’s antenatal information. It is simple, cheap, and effective. It is uncommon for patients to lose their records. The clinical record is then always available wherever the patient presents for care. The clinic need only record the patient’s personal details such as name, address and age together with the dates of her clinic visits and the result of any special investigations.
On the one side of the card are recorded the patient’s personal details, history, estimated gestational age, examination findings, results of the special investigations, plan of management, and proposed future family planning. On the other side are recorded all the maternal and fetal observations made during pregnancy.
It is important that all antenatal women have a hand-held Maternity Case Record.
1-56 What topics should you discuss with patients during the health education sessions?
The following topics must be discussed:
- Danger symptoms and signs.
- Dangerous habits, e.g. smoking or drinking alcohol.
- Healthy eating.
- Family planning.
- Care of the newborn infant.
- The onset of labour and labour itself must also be included when the patient is a primigravida.
- Avoiding HIV infection or getting counselling if HIV positive.
1-57 What symptoms or signs, which may indicate the presence of serious complications, must be discussed with patients?
- Symptoms and signs that suggest abruptio placentae:
- Vaginal bleeding.
- Persistent, severe abdominal pain.
- Decreased fetal movements.
- Symptoms and signs that suggest pre-eclampsia:
- Persistent headache.
- Flashes before the eyes.
- Sudden swelling of the hands, feet or face.
- Shortness of breath (dyspnoea).
- Symptoms and signs that suggest preterm labour:
- Rupture of the membranes.
- Regular uterine contractions before the expected date of delivery.
- Supplements to be taken
- Iron supplements should be routinely taken as explained in sections 13-19 to 13-22.
- Calcium supplementation decreases the risk of developing pre-eclampsia, especially in areas where dietary intake of calcium is low. Calcium 1 to 1.5 grams daily is recommended (two to three 500 mg tablets daily). Calcium tablets need to be taken 2 hours apart from iron tablets as calcium reduces the absorption of iron.
- Folic acid supplementation is required for mothers with a history of previous babies with neural tube defects and women living in endemic malaria areas. One 5 mg tablet should be taken daily from the time pregnancy is planned.
Managing women with HIV infection
1-58 What is HIV infection and AIDS?
AIDS (Acquired Immune Deficiency Syndrome) is a severe chronic illness caused by the human immunodeficiency virus (HIV). Women with HIV infection can remain clinically well for many years before developing signs of the disease. Severe HIV disease is called AIDS. These patients have a damaged immune system and often die of other opportunistic infections such as tuberculosis.
1-59 Is AIDS an important cause of maternal death?
As the HIV epidemic spreads, the number of pregnant women dying of AIDS has increased dramatically. In some countries, such as South Africa, AIDS is now the commonest cause of maternal death. Therefore all pregnant women must be screened for HIV infection.
- The Second, Third and Forth Interim Report on Confidential Enquiries into Maternal Deaths in South Africa showed that AIDS was the commonest cause of maternal death.
All pregnant women must be screened for HIV infection as AIDS is the commonest cause of maternal death in South Africa.
1-60 Does pregnancy increase the risk of progression from asymptomatic HIV infection to AIDS?
Pregnancy appears to have little or no effect on the progression from asymptomatic to symptomatic HIV infection. However, in women who already have symptomatic HIV infection, pregnancy may lead to a more rapid progression to AIDS.
1-61 How is the severity of HIV infection classified?
The severity and progression of HIV infection during pregnancy can be monitored by:
- Assessing the clinical stage of the disease
- Stage 1: Clinically well.
- Stage 2: Mild clinical problems.
- Stage 3: Moderate clinical problems.
- Stage 4: Severe clinical problems (i.e. AIDS).
- Measuring the CD4 count in the blood. A falling CD4 count is an important marker of progression in HIV infection. It is an indicator of the degree of damage to the immune system. The normal adult CD4 count is 700 to 1100 cells/mm³. A CD4 count equal or below 350 cells/mm³ indicates severe damage to the immune system.
The CD4 count is an important marker of the severity and progression of HIV infection during pregnancy.
1-62 What clinical signs suggest stage 1 and 2 HIV infection?
- Persistent generalised lymphadenopathy is the only clinical sign of stage 1 HIV infection.
- Signs of stage 2 HIV infection include:
- Repeated or chronic mouth or genital ulcers.
- Extensive skin rashes.
- Repeated upper respiratory tract infections such as otitis media or sinusitis.
- Herpes zoster (shingles).
1-63 What are important features suggesting stage 3 or 4 HIV infection?
- Features of stage 3 HIV infection include:
- Unexplained weight loss.
- Oral candidiasis (thrush).
- Cough, fever and night sweats suggesting pulmonary tuberculosis.
- Cough, fever and shortness of breath suggesting bacterial pneumonia.
- Chronic diarrhoea or unexplained fever for more than 1 month.
- Pulmonary tuberculosis
- Features of stage 4 HIV infection include:
- Severe weight loss.
- Severe or repeated bacterial infections, especially pneumonia.
- Severe HIV-associated infections such as oesophageal candidiasis (which presents with difficulty swallowing) and Pneumocystis pneumonia (which presents with cough, fever and shortness of breath).
- Malignancies such as Kaposi’s sarcoma.
- Extrapulmonary tuberculosis (TB).
1-64 How should pregnant women with a positive HIV screening test be managed?
It is very important to identify women with HIV infection as soon as possible in pregnancy so that they can be carefully assessed and their management can be planned. HIV positive pregnant women need to be commenced on highly active antiretroviral (HAART) treatment. The HIV management should be integrated into the rest of the antenatal care. All women with a positive HIV screening test must have their CD4 count determined as soon as the HIV screening result is obtained.
Determine and note the clinical stage of the disease on the antenatal record.
All HIV-positive women must be commenced on HAART.
1-65 What antiretroviral (ARV) treatment is given during pregnancy?
ARV treatment aims at improving the mother’s health and reducing the risk of the mother infecting her fetus and newborn infant with HIV (prevention of mother-to-child transmission or PMTCT). ARV treatment should be started at 14 weeks or as soon as possible thereafter and will continue as lifelong treatment. It will reduce the risk of HIV transmission from mother to infant to less than 2%, compared to 30% when ARVs are not taken.
For treatment a fixed dose combination (FDC) pill is taken daily, usually at bedtime.
- WHO option A , which is no longer used in South Africa, consists of zidovudine (AZT) 300 mg orally twice daily from 14 weeks gestation. In addition a single dose of nevirapine 200 mg is given to the mother at the onset of labour and AZT 300 mg 3 hourly is given during labour. In addition a single dose of Truvada, a combination of tenofovir (TNF) and emtricitabine (FTC), must be given to the mother during or immediately after labour to prevent nevirapine resistance in the mother. Option A will be used for women diagnosed HIV-positive during labour or women who defaulted on their ARV treatment.
1-66 What is antiretroviral treatment?
The aim of ARV treatment is to lower the viral load and allow the immune system to recover. This will both reduce the risk of HIV transmission to the infant and to treat the mother’s HIV infection. ARV treatment consists of taking tenofovir (TDF) 300 mg, emtricitabine (FTC) 200 mg and efavirenze (EFV) 600 mg as a FDC tablet daily.
Women who are already on ARV treatment when they book for antenatal care should continue on their ARV treatment during the pregnancy. If not already on FDC, their ARV’s may be changed:
- Women on TDF, lamuvidine (3TC) and EFV can be changed to FDC.
- Women on Zidovidine (AZT), 3TC and EFV can remain on the regimen.
- Women on TDF, 3TC and nevirapine (NVP) can remain on the regimen.
A fixed dose combination of antiretroviral drugs (FDC) is used for HIV treatment during pregnancy.
1-67 Can an HIV-positive woman be cared for in a primary-care clinic?
Most women who are HIV positive are clinically well with a normal pregnancy. Others may only have minor problems (stage 1 or 2). These women can usually be cared for in a primary-care clinic throughout their pregnancy, labour, and puerperium provided they remain well and their pregnancy is normal. Women with a pregnancy complication should be referred to hospital as would be done with HIV-negative patients. Women with severe (stage 3 or 4) HIV-related problems or severe treatment side effects will need to be referred to a special HIV clinic or hospital.
Most HIV-positive women can be managed at a primary-care clinic during pregnancy.
1-68 How are pregnant women with HIV infection managed at a primary-care clinic?
The management of pregnant women with HIV infection is very similar to that of non-pregnant adults with HIV infection. The most important step is to identify those pregnant women who are HIV positive.
The principles of management of pregnant women with HIV infection at a primary-care clinic are:
- Make the diagnosis of HIV infection by offering HIV screening to all pregnant women at the start of their antenatal care.
- Assess the CD4 count in all HIV-positive women as soon as their positive HIV status is known.
- Screen for clinical signs of HIV infection and clinical staging at each antenatal visit.
- Screen for symptoms of TB.
- Good diet. Nutritional support may be needed.
- Emotional support and counselling.
- Start ARV treatment with FDC on day of diagnosis if there are no contra-indications.
- Early referral if there are pregnancy or HIV complications.
1-69 What preparation is needed for antiretroviral treatment?
Preparing a patient to start ARV treatment is very important. This requires education, counselling and social assessment before ARV treatment can be started. These patients must have regular clinic attendance and must learn about their illness and the importance of excellent adherence (taking their ARV drugs at the correct time every day). They also need to know the side effects of ARV drugs and how to recognise them. A careful history, general examination and some blood tests are also needed. ARV treatment should start on the day of diagnosis. TDF is contra-indicated with chronic renal disease and EFV with psychiatric disease. A serum creatinine must be requested and the result followed up one week later.
1-70 How should pregnant women on antiretroviral treatment be managed?
The national drug protocol using a FDC should be followed. It is very important that staff at the antenatal clinic are trained to manage women with HIV infection. They should work together with the local ARV clinic or infectious disease clinic of the local hospital.
1-71 What drugs are used when tenofovir and efavirenze are contra-indicated?
- With chronic renal disease and a serum creatinine of 85 mmol/l or more, TDF and FTC is replaced with AZR and 3TC.
- With psychiatric disease, EFV is replaced by a protease inhibitor (e.g. Aluvia).
1-72 What are the side effects of antiretroviral drugs?
Pregnant women on ARV treatment may experience side effects to the ARV drugs. These are usually mild and occur during the first six weeks of treatment. However, side effects may occur at any time that patients are taking ARV drugs. It is important that the staff at primary-care clinics are aware of these side effects and that they ask for symptoms and look for signs at each clinic visit.
Common early side effects during the first few weeks of starting ARV drugs include:
- Lethargy, tiredness and headaches.
- Nausea, vomiting and diarrhoea.
- Muscle pains and weakness.
These mild side effects usually disappear on their own. They can be treated symptomatically. It is important that ARVs are continued even if there are mild side effects.
EFV may cause insomnia (cannot sleep), abnormal dreams and rarely psychiatric symptoms.
More severe side effects that may be fatal include:
- TDF may cause decreased renal function.
- NVP may cause severe skin rashes. All patients with severe skin rashes must be urgently referred to hospital. EFV can cause milder skin rashes.
- AZT suppresses bone marrow and may cause anaemia. There may also be a reduction in the white cell and platelet count.
- NVP and EFV may cause Hepatitis.
- Lactic acidosis is a late but serious side effect, most often caused by stavudine (d4T), but also caused by AZT and TDF. Lactic acidosis presents with weight loss, tiredness, nausea, vomiting, abdominal pain and shortness of breath in patients that have been well and on ARV treatment for months.
Staff at primary-care clinics must be aware of and look out for these very important side effects.
1-73 Is HIV and TB co-infection common in pregnancy?
Tuberculosis (TB) is common in patients with HIV who have a weakened immune system. Therefore co-infection with both HIV and TB bacilli is common during pregnancy in communities with a high prevalence of HIV and TB. Symptomatic screening for TB must be done at each visit by weighing the patient, to check for weight loss, and by asking her about a chronic cough, fever or profuse night sweats. If any one of these are present further investigations for TB are required.
TB is treated with four drugs (rifampicin, isoniazid, pyrizinamide and ethambutol) which may interact and increase the adverse effects of ARV drugs. Treatment of both HIV and tuberculosis should be integrated with routine antenatal care whenever possible.
- The negative predictive value of symptomatic screening is 97%. Therefore a negative screen reliably excludes TB. Further investigations for TB include sputum for microscopy and GeneXpert test as well as a single posterior-anterior chest X-ray with the fetus screened off with a lead apron.
Case study 1
A 36-year-old gravida 4 para 3 patient presents at her first antenatal clinic visit. She does not know the date of her last menstrual period. The patient says that she had hypertension in her last two pregnancies. The symphysis-fundus height measurement suggests a 32-week pregnancy. At her second visit, the report of the routine cervical smear states that she has a low-grade cervical intra-epithelial lesion.
1. Why is her past obstetric history important?
Because hypertension in a previous pregnancy places her at high risk of hypertension again in this pregnancy. She must be carefully examined for hypertension and proteinuria at this visit and at each subsequent visit. This case stresses the importance of a careful history at the booking visit.
2. How accurate is the symphysis-fundus height measurement in determining that the pregnancy is of 32 weeks duration?
This is the most accurate clinical method to determine the size of the uterus from 18 weeks gestation. If the uterine growth, as determined by symphysis-fundus measurement, follows the curve on the antenatal card, the gestational age as determined at the first visit is confirmed.
3. Why would an ultrasound examination not be helpful in determining the gestational age?
Ultrasonology is accurate in determining the gestational age only up to 24 weeks. Thereafter, the range of error is virtually the same as that of a clinical examination.
4. What should you do about the result of the cervical smear?
The cervical smear must be repeated after 9 months. It is important to write the result in the antenatal record and to indicate what plan of management has been decided upon.
Case study 2
At booking, a patient has a positive syphilis rapid test with a titre of 1:4. She has had no illnesses or medical treatment during the past year. By dates and abdominal palpation she is 26 weeks pregnant.
1. What does the result of this patient’s syphilis rapid test indicate?
The positive syphilis rapid test indicates that the patient may have syphilis or may have had syphilis that was fully treated.
2. What further test is needed to confirm or exclude a diagnosis of syphilis?
If possible, the patient must have a RPR or VDRL test. A positive result with a titre of 1:16 or more confirms the diagnosis of syphilis. If these tests are not available, the patient must be treated for syphilis. RPR and VDRL titres of less than 1:16 may be present with recent infection or recent treatment as well as with latent syphilis. Full treatment is given unless the patient and her partner have been fully treated in the past 3 months.
3. Why is the fetus at risk of congenital syphilis?
Because the spirochaetes that cause syphilis may cross the placenta and infect the fetus.
4. What treatment is required if the patient has syphilis?
The patient should be given 2.4 million units of benzathine penicillin (Bicillin LA or Penilente LA) intramuscularly weekly for 3 weeks. Half of the dose is given into each buttock. Benzathine penicillin will cross the placenta and also treat the fetus.
5. What other medical conditions is this patient likely to suffer from?
She may have other sexually transmitted diseases such as HIV.
Case study 3
A healthy primigravida patient of 18 years booked for antenatal care at 22 weeks pregnant. Her rapid syphilis and HIV tests were negative. Her Rh blood group is positive according the Rh card test. She is classified as at low risk for problems during her pregnancy.
1. What is the best time for a pregnant woman to attend an antenatal-care clinic for the first time?
If possible, all pregnant women should book for antenatal care within the first 12 weeks. The duration of pregnancy can then be confirmed with reasonable accuracy on physical examination, medical problems can be diagnosed early, and screening tests can be done as soon as possible.
2. When should this patient return for her next antenatal visit?
She should attend at 28 weeks.
3. What important complications should be looked for in this patient at her 28 week visit?
Anaemia, early signs of pre-eclampsia, a uterus smaller than expected (suggesting intra-uterine growth restriction), or a uterus larger than expected (suggesting multiple pregnancy). A history of antepartum haemorrhage should also be asked for.
4. When should she attend antenatal clinic in the last trimester if she and her fetus remain normal?
The next visit should be at 34 weeks, and then every 2 weeks until 41 weeks.
Case study 4
A 24-year-old gravida 2 para 1 attends the booking antenatal clinic and is seen by a midwife. The previous obstetric history reveals that she had a Caesarean section at term because of poor progress in labour. She is sure of her last menstrual period and is 14 weeks pregnant by dates. On abdominal palpation the height of the uterine fundus is halfway between the symphysis pubis and the umbilicus.
1. What further important information must be obtained about the previous Caesarean section?
The exact indication for the Caesarean section must be found in the patient’s hospital notes. In addition, the type of uterine incision made must be established, i.e. whether it was a transverse lower segment or a vertical incision.
2. Why is it important to obtain this additional information?
If the patient had a Caesarean section for a non-recurring cause and she had a transverse lower segment incision, she may be allowed a trial of labour.
3. In which risk category would you place this patient?
She should be placed in the intermediate category.
4. How must you plan this patient’s antenatal care?
Her next visit must be arranged at a hospital. If possible, the hospital where she had the Caesarean section so that the required information may be obtained from her folder. Then she may continue to receive her antenatal care from the midwife at the clinic until 36 weeks gestation. From then on the patient must again attend the hospital antenatal clinic where the decision about the method of delivery will be made.
5. Which of the two estimations of the duration of pregnancy is the correct one?
A fundal height measurement midway between the symphysis pubis and the umbilicus suggests a gestational age of 16 weeks. According to her dates, the patient is 14 weeks pregnant. As the difference between these two estimations is less than 3 weeks, the duration of pregnancy as calculated from the patient’s dates must be accepted as the correct one.