Antenatal Care Flashcards
To understand the risks of drug treatment in pregnancy
There are many medications which carry an associated risk of teratogenicity
- Antiepileptics
- Retinoids (isotretinoin)
- Antibiotics: Trimethoprim, tetracyclines
- Warfarin
- Propanolol
To understand the risks of substance abuse in pregnancy
Smoking
- CO causes the oxygen dissociation curve to shift to the left, decreasing oxygen transfers to the foetus
- Nicotine acts as a vasoconstrictor on the uteroplacental vasculature
- Smoking may affect placental structure: irregular thickening and reduced calibre of foetal capillaries
- Causes low birthweight and reduced crown-heel length
Alcohol intake
- FAS – follows maternal consumption of > 8 units/day
- Increased risk of miscarriage, congenital abnormalities, premature labout and SGA
Illicit drug use
- May of the adverse effects of illicit drug use are related to lifestyle and malnutrition
- Heroin addiction → IUGR, perinatal death, pre-term labour, neonatal withdrawal manifestations
- Amphetamine → Increased risk of miscarriage, preterm birth, growth restriction, placental abruption
- Cocaine → Cardiac arrhythmias and CNS damage in mothers, placental abruption, foetal growth restriction, preterm labour
To understand the booking visit and routine investigations
Booking visit: Should take place within the first 10 weeks of pregnancy
Information
- Supplements: 400 micrograms of folate up to 12 weeks, Vitamin D
- Smoking and substance cessation
- Diet and exercise
Blood tests
- Blood group, alloantigens, rhesus D status
- FBC: ?Anaemia
- Serology: HIV, hepatitis, syphillus
- Haemoglobinopathies: Sickle cell anaemia, thalassaemia
Other tests:
- Weight and height for BMI
- BP
- Urine dip
- Urine MC&S (checking for asymptomatic urine infection)
To be able to perform pregnancy dating and calculation of gestational age
Will use a date calculating wheel to do so in OSCE
To know schedules of routine antenatal care
To have a detailed understanding of the use of anti-D in prophylaxis of Rhesus immunisation
Anti-D should be provided for Rhesus-D negative mothers. Anti-D acts by binding to surface D antigens on foetal RBCs that have crossed into maternal circulation, preventing maternal antibodies against foetal cells being produced.
Maternal rhesus status is checked at booking and at 28 weeks.
Anti-D is administered to mothers at 28 and 34 weeks, or a single large dose at 28 weeks. It should also be administered within 72 hours of a potentially sensitising event in mothers of gestation > 12 weeks.
To have detailed knowledge of the diagnosis, management and implications of hypertensive disorders of pregnancy
To have detailed knowledge of the diagnosis, management and implications of gestational diabetes
Diagnosis:
- Investigation is required after urine dips reveals +2 glucose on 1 occasion or +1 glucose on 2 occasions
- 75g 2-hour OGTT1 > 7.8 mmol/L
- Fasting plasma glucose > 5.6 mmol/L
Management
For fasting plasma glucose < 7.0 mmol/L: Offer a 2 week trial of diet (low glycaemic index) and exercise.
If blood sugars are not improved after this trial then metformin is indicated.
If fasting plasma glucose is > 7 mmol/L then immediate treatment with metformin is indicated.
Self-monitoring of blood sugars through capillary BMs.
Implications
- Foetal macrosomia
- Increased risk of birth trauma and shoulder dystocia due to increased foetal size
- Polyhydramnios
- Neonatal hypoglycaemia
1:Offered to mothers at risk of GD between 24 - 28 weeks gestation or immediately to those with previous GD.
Risk factors for the development of GD should be assessed for: BMI > 30 kg/m2, previous GD, FHx of diabetes, previous macrosomic baby > 4.5 kg, majority ethnic family origin with a high prevalence of diabetes
To have a detailed knowledge of the diagnosis, management and implications of antepartum haemorrhage
In normal pregnancy demonstrate understanding of preconceptual care, use of lifestyle changes, folic acid and nutritional requirements
Pre-conceptual care
- Folic acid should be taken prior to conception (400 micrograms or 5 mg for high risk)
- If trying to conceive then certain medications should be ceased prior to this
- Ensure good health: Exercise, diet, smoking cessation, alcohol intake
Lifestyle changes
- Smoking cessation and no alcohol consumption
- 30 minutes of moderate exercise a day
- Certain foods should be avoided: Unpasteurised milk/cheeses, mould ripened and soft blue cheeses, raw/uncooked meats, pate, liver, eggs without the british lion on, uncooked fish/shellfish, no more than 200mg of caffeine per day,
Folic acid
- Should be taken up to 12 weeks gestation
Nutritional requirements
In normal pregnancy, to demonstrate understanding of the basics of genetic inheritance and include examples of common inherited disorders, e.g. cystic fibrosis, haemoglobinopathies
Understand screening for foetal abnormality, including chromosomal
- Combined test at 10-14 weeks: Uses bloods (PAPP-A and hCG) and USS (nuchal transluency) to identify any abnormalities suggestive of Down syndrome, Edward’s (18) or Patau’s (13)
- Anomaly scan at 20 weeks: Checking for any structural abnormalities e.g. renal agenesis, cardiac malformations etc.
- Quadruple test at 14 - 20 weeks: May be performed if the combined test was not feasible (i.e. nuchal translucency couldn’t be assessed). Serum levels of hCG, AFP, inhibin A and uE3 are analysed.
- If the above tests provide reason to suspect an increased risk of abnormality amniocentesis (15-20 weeks) or CMV (< 15 weeks) can be performed, acting as diagnostic testing
To be aware of the risks and management of multiple pregnancy
Risks:
- Preterm birth
- Foetal growth restriction
- Increased risk of chromosomal abnormalities
- Increased risk of perinatal death
Further risks for monochorionic twins:
- Twin-to-twin transfusion syndrome (TTTS)
Further risks for monoamnioic twins:
- Cord entanglement
Maternal complication also present with an increase incidence: Anaemia, hyperemesis gravidarum, hypertension, pre-eclampsia, placenta praevia, antepartum and postpartum haemorrhage, operative delivery and maternal mortality
Management:
- ?Consultant led care
- Chorionicity should be determined at the 12 week scan (as it most accurately determined before 14 weeks)
- Increased serial growth scans (exact schedule dependent on whether dichorionic or monochorionic)
- Finalise the mode of delivery at 32 weeks. C-section is offered for all twin pregnancies.
- Pregnancies should not be allowed to progress beyond 37-38 weeks gestation
- Intrapartum care: CTG monitoring, syntocinon may be administered to aid delivery of the second twin, syntocinon after delivery is recommended due to increased risk of postpartum haemorrhage (because of the enlarged uterus)
To be aware of the risks and management of breech presentation
Risks:
- Cord prolapse
- Entrapment of the head following delivery of the body
- Increased risk of mortality
- Birth trauma
Management:
- ECV
- To be offered at 37+0 (or 36+0 in nulliparous women)
- 50% success rate. Can be painful
- Tocolytics (betamimetics) may be administered to increase the likelihood of success
- Electronic foetal monitoring and testing for fetomaternal haemorrhage (in Rhesus negative mothers) should be performed following the procedure
- Risks include placental rupture, uterine rupture and pre-term labour
- Contraindications: Foetal compromise, multiple pregnancy, PV delivery prevented e.g. placenta praevia, ruptured membranes, recent antepartum haemorrhage
- PV delivery:
- > a third of PV delivery attends end in emergency C-section
- Elective C-section:
Types of breech presentation: Frank, complete, footling
To be aware of the risks and management of prolonged pregnancy
Risks:
- Increased risk of intrauterine foetal death
- Growth restriction due to placental insufficiency
- Foetal macrosomnia:
- Increased risk of shoulder dystocia, obstructed labour, instrumental delivery, perineal trauma, prolonged labour, birth trauma
- Increased risk of meconium aspiration
- Neonatal seziures/encephalopathy/acidaemia
Management:
- Induction offered from 41+0
- Membrane sweep
- Vaginal prostaglandins
- Amniotomy
- If induction is refused then there should be twice weekly CTG and estimation of maximum amniotic fluid pool from 42+0 weeks
To be aware of the principles of foetal monitoring
- Assess foetal growth
- Assess for congenital abnormalities/genetic conditions
- Assess placenta flow and amniotic fluid pool
To be aware of the implications of pre-existing disease in pregnancy
Can cause an increased risk of complications, dependent upon the pre-existing condition.
*See separate topics
To demonstrate knowledge on the diagnosis, management and implications of preterm labour/rupture of membrane
Diagnosis:
- History: PV fluid, abdominal pain/contractions
- Examination:
- Speculum and PV examination to look for amnioitic fluid
- Abdominal palpation to check foetal position
- Investigations:
- Foetal fibronectin test
- TVS to assess cervical effacement
- High vaginal swab for infection1 (via speculum), CRP
- CTG
Management:
- If presenting between 24-34 weeks steroids should be administered, +/- tocolytics to allow for administration
- Antibiotics if in comfirmed labour and infection detected
- C-section if indicated
Implications:
- Increased risk of neonatal mortality and morbidity
- Complications associated with prematurity: RDS, NEC, CP
1: Chorioamnionitis presents with abdominal pain, fever, tachycardia, uterine tenderness and coloured/offensive liquor
To demonstrate knowledge of the diagnosis, management and implications of anaemia
Diagnosis
- FBC and serum ferritin levels performed at booking and at 28 weeks
- Hb level < 110 g/l in the first trimester or < 105 g/l in the second and third trimester indicates anaemia
- Maternal symptoms may be experienced, such as fatigue, dyspnoea, pallor, weakness, headaches
Management
- Oral iron supplementation
- Parenteral may be considered if there is no improvement
- Tranfusion
Implications
- Maternal implications: Reduced immune function
- Effects on the foetus: Increased risk of iron deficiency anaemia in the first 3/12 of life
To demonstrate knowledge of the diagnosis, management and implications of rhesus isoimmunisation
Diagnosis:
- Unsensitised women are diagnosed antenatally through routine screening at the booking appointment (10-14 weeks) and tested again at 28 weeks
- Bloods taken for rhesus status, blood group and antibodies
- Rhesus negative mother
- Mother may have been previously sensitised, in which case anti-D
Management:
- Administration of Anti-D to the mother, as either one dose at 28 weeks or 2 doses (28 and 34 weeks)
- Anti-D acts to bind the foetal RBCs that have crossed into the maternal circulation, preventing the synthesis of maternal antibodies against the rhesus positive cells
- Anti-D should also be administered within 72 hours of any potentially sensitising events such as aborption, intrapartum haemorrhage, ECV and CVS/amniocentesis
- At birth, the neonates blood group should be checked. If the neonate is rhesus positive then an additional dose of anti-D should be given to the mother and a kleihauer test performed, to see if any additional ‘mop up’ anti-D is required
Implications:
- Neonatal haemolysis → neonatal jaundice
- Haemolytic disease of the newborn
- Hydrops foetalis
- In utero transfusion or early delivery required
To demonstrate knowledge of the diagnosis, management and implications of infections in pregnancy.
Diagnosis
- Antenatal screening at booking for HIV, hepatitis and syphilis
- UTI may present as abdominal pain and intrapartum haemorrhage
- Maternal symptoms/exposure/known recurrences (e.g. HSV)
Management
-
Implications
- If there is maternal immunity to the infection (IgG present) then the foetus will not be affected by the disease
- Toxoplasmosis: Chorioretinitis, intracranial calcification, hydrocephalus.
- Syphilis: Vertical transmission if no maternal treatment.
- Erythema infectiosum: In early pregnancy miscarriage and stillbirth may result. Later in pregnancy infection causes foetal anaemia, which can lead to high output cardiac failure, fluid retention and oedema.
- Chicken pox: Congenital varicella syndrome, consisting of chorioretinitis, cataracts, neurological deficit and limb hypoplasia
- Chlamydia: Mucopurulent conjunctivitis
- Rubella: Congential rubella syndrome consisting of congenital glaucoma, cataracts, cardiac malformations, ‘blueberry muffin baby’, hepatosplenomegaly, developmental delay and deafness
- CMV: 90% of newborns are asymptomatic, presenting later with progressiv hearing loss. 10% present with jaundice, splenomegaly and petechiae from thrombocytopenia. Cytomegalic inclusion disease affects the neurological, ophthalmic, endocrine and haematological systems.
- HSV: Neonatal HSV infection sees chorioretinitis, neurological problems and vesicular skin eruptions
To demonstrate knowledge of the diagnosis, management and implications of thromboembolic disease.
Diagnosis
- Deep vein: Swelling, tenderness, redness, unilateral oedema in the affected area
- Compression duplex US
- PE: Sudden onset dyspnoea, ECG changes
- ECG, CXR, +/- CTPA
- D-dimer should not be used in pregnancy
Management
- Anticoagulants: LMWH
- Baseline blood tests are required prior to administration - FBC, coagulation screen, U&Es and LFTs
- Treatment should be continued for the rest and pregnancy and at least 6/52 post-partum, until 3/12 of treatment has been given. May consider LMWH or warfarin, both can be used when breastfeeding
- Graduated compression stockings and elevation of the affected limb
Implications
- Risk of the thrombus dislodging and travelling to the cerebral circulation, where it may cause a stroke
To understand the legal rights of and provisions for pregnant women
In complicated pregnancies, to be aware of how to perform diagnostic tests for fetal abnormality.
Screening tests to assess risk:
Combined test at the dating scan (10-14 weeks): Nuchal translucency on USS and bloods (PAPP-A and hCG)
Quadruple test (15-20 weeks): Bloods
Diagnosis:
Amniocentesis (15-20 weeks) or CVS (< 15 weeks): Allows for diagnosis
- Risks: Discomfort, pain, bleeding1, miscarriage (1/200 miscarry)
1: More common following transvaginal CVS
