Antenatal Care Flashcards
PACES: Pre-pregnancy counselling for people with epilepsy
Aim for monotherapy where possible and emphasise the importance of maintaining good compliance
High dose folic acid (5 mg OD)
Provide advice about the risk of congenital malformations
What AED should be avoided in all girls and women of child bearing age?
Sodium valproate is highly teratogenic so should be avoided in all girls and women of child-bearing age
What are antiepileptic drugs associated with an increased risk of?
Neural tube defects
Cleft palate
Congenital heart defects
Safest AEDs in pregnancy
Lamotrigine
Levetiracetam
Carbamazepine
Can you breastfeed with AEDs in pregnancy?
Yes, all are safe
Differentials for seizures in pregnancy
Eclampsia
Intracranial infection (e.g. encephalitis)
Space-occupying lesion
Cerebrovascular accident
Thrombotic thrombocytopaenic purpura
Overdose
Metabolic abnormalities (e.g. hypoglycaemia)
NOTE: NOTE: it is important to be wary of other causes of seizures in pregnancy even if a patient has a background of epilepsy
What is sampled in chorionic villus sampling?
Foetal trophoblast cells
What route is chorionic villus sampling done via?
transabdominal or transvaginal route
What is chorionic villus sampling associated with?
small risk of miscarriage
When is chorionic villus sampling done in comparison to amniocentesis?
Can be performed earlier in the pregnancy than amniocentesis
What is amniocentesis?
Amniocentesis involves passing a needle into the amniotic sac and aspirating around 15-20 mL of fluid that contains these cells
NOTE: The amniotic fluid contains amniocytes and fibroblasts that have shed from the foetal membranes, skin and genitourinary tract
What is cordocentesis?
Involves passing a needle into the umbilical cord and sampling some foetal blood
Usually used in suspected severe foetal anaemia and thrombocytopaenia
Risk of amniocentesis
Associated with a small risk of miscarriage
Risk of cordocentesis
Associated with a risk of miscarriage
Prenatal genetic test with biggest risk of miscarriage
cordocentesis
Only prenatal genetic test with no risk of miscarriage
Cell-free foetal DNA (cffDNA)
When is cordocentesis typically used?
Usually used in suspected severe foetal anaemia and thrombocytopaenia
What is cell-free foetal DNA?
Foetal DNA is extracted from a maternal blood sample
It may be used to determine the foetal blood group and Rhesus status and to determine the sex of the foetus
What is cell-free foetal DNA typically used for?
used to determine the foetal blood group and Rhesus status and to determine the sex of the foetus
Safest prenatal genetic test
Cell free foetal DNA
Most dangerous prenatal genetic test
Cordocentesis - biggest risk of miscarriage
What is Haemolytic disease of the newborn?
Haemolytic disease of the newborn caused by the generation of maternal antibodies against RhD antigen on foetal red cells.
Pathophysiology of HDN
If the barrier between the circulations of a RhD-negative mother and a RhD-positive baby is breached, it can sensitise the maternal immune system against RhD.
The initial antibodies produced are IgM, which cannot cross the placenta and, so, do not cause any issues during the initial pregnancy.
IgG antibodies will be produced later as the immune response matures.
If the mother becomes pregnant with another RhD positive foetus, the IgG antibodies will then be able to cross the placenta, destroy foetal red cells and cause severe foetal anaemia (resulting in hydrops fetalis).
What are initial antibodies produced in HDN?
IgM
What are the mature antibodies produced in HDN that are able to cross the placenta?
IgG
What does HDN lead to?
Hydrops fetalis
Examples of sensitising events
Invasive prenatal diagnosis (e.g. amniocentesis)
Antepartum haemorrhage
External cephalic version
Ectopic pregnancy
Surgical evacuation of molar pregnancy
Intrauterine death or stillbirth
Miscarriage after 12 weeks’ gestation
Surgical termination of pregnancy
What is management of HDN?
Anti-D Immunoglobulin
How does Anti-D Immunoglobulin work?
Works by destroying foetal red cells within the maternal circulation before the maternal immune system has a chance to generate antibodies against the RhD antigen
Indications for anti-D immunoglobulin
Antepartum Haemorrhage
Abdominal Trauma in Pregnancy
Amniocentesis or Chorionic Villus Sampling
Surgical Management of Ectopic Pregnancy
Surgical Management of Miscarriage
Evacuation of Molar Pregnancy
All RhD-negative Women Undergoing Termination of Pregnancy
External Cephalic Version
What is Kleihauer test?
Used in some situations to measure the extent to which foetal blood mixed with the maternal circulation
This allows titration of the dose of anti-D immunoglobulin
Who is routine anti-D immunoglobulin given to?
Given to RhD-negative women at 28 weeks’ gestation (and may also be given at 34 weeks’ gestation
How many antenatal appointments are there typically during pregnancy?
10 visits in all FIRST pregnancies if uncomplicated
7 visits in subsequent pregnancies if uncomplicated
What tests are offered at antenatal booking?
Ultrasound Scans
Dating Scan: 10-14 Weeks
Measures crown-rump length to determine gestational age and to establish estimated delivery date
Measures nuchal translucency as part of antenatal screening
Anomaly Scan: 18-21 Weeks
Determine placental site
Blood Test Screen
Infections: HIV, Hepatitis B and Syphilis
Haemoglobinopathies: Sickle Cell Disease and Thalassemia
Establish RhD status
When is the dating scan done? what is it for?
Dating Scan: 10-14 Weeks
Measures crown-rump length to determine gestational age and to establish estimated delivery date
Measures nuchal translucency as part of antenatal screening
When is the anomaly scan done? What is it for?
Anomaly Scan: 18-21 Weeks
Determine placental site
What is screened for in the blood test screen in antenatal booking?
Infections: HIV, Hepatitis B and Syphilis
Haemoglobinopathies: Sickle Cell Disease and Thalassemia
Establish RhD status
What infections are screened for in antenatal booking?
Infections: HIV, Hepatitis B and Syphilis
What haemoglobinopathies are screened for at antenatal booking?
Haemoglobinopathies: Sickle Cell Disease and Thalassemia
What must be established at antenatal booking?
RhD status
PACES: Key questions to ask at booking visit
Last Menstrual Period
Any previous pregnancies (incl. Miscarriages)
Past medical and surgical history
Ethnic origins of patient and partner (screen for inherited conditions and gain understanding of cultural factors affecting pregnancy)
Employment of patient and partner
Current living situation
How the patient is feeling about the pregnancy
PACES: Common Sx in pregnancy
Nausea
Heartburn
Constipation
SOB
Dizziness
Swelling
Backache
Abdominal discomfort
Headache
PACES: Risks of smoking in pregnancy
FGR
Preterm labour
Placental abruption
Intrauterine foetal death
Provide support through smoking cessation programmes
PACES: Advice regarding diet in pregnancy
DO NOT eat for two - maintain normal portion side and try avoid snacking
Recommend high fibre foods (oats, beans, lentils, grains)
Base meals on starchy substances (potatoes, bread, pasta, rice)
Restrict intake of fried food and high sugars
PACES: Advice regarding exercise in pregnacny
Aerobic and strength conditioning is safe to continue and may help recovery after delivery and improve overall wellbeing
Avoid contact sports
Pelvic floor exercises can reduce risk of incontinence
PACES: Advice regarding breastfeeding
Recommend initiation of breastfeeding within an hour of birth
Recommend exclusive breastfeeding for the first 6 months
Can continue breastfeeding up to 2 years of age
Early education about breastfeeding is advocated to improve uptake and to engage women with breastfeeding services
Options for delivery
Home birth
Midwifery units or birth centres
Hospital birth centres
Advantages about home birth
ADVANTAGES: familiar surroundings, no interruption of labour to go to hospital, no separation from family members, continuity of care
Disadvantages of home birth
DISADVANTAGES: 45% of first-time mothers are transferred to hospital, poor perinatal outcome is twice as likely for home births, limited analgesic options
Advantages of midwifery units or birth centres
ADVANTAGES: continuity of care, fewer interventions, convenient location
Disadvantages of midwifery units or birth centres
DISADVANTAGES: 40% of nulliparous women require transfer to a hospital birth centre, limited access to analgesic options
Advantages of hospital birth centre
ADVANTAGES: trained personnel and facilities available to manage any potential complications
Disadvantages of hospital birth centre
DISADVANTAGES: lack of continuity of care, greater likelihood of intervention
Summary of antenatal appointments
How is trisomy 21 screened for in pregnancy?
First trimester - combined test
Second trimester - quadruple test
What is the combined test for? when is it offered?
for trisomy 21 screeening,Offered from 11+3 to 13+6 weeks
What is in the combined test?
Nuchal Translucency (NT)
Increased in trisomy 21
Maternal b-hCG and PAPP-A
Trisomy 21 is associated with high b-hCG and low PAPP-A
GET INCREASED B-HCG AND NUCHAL TRANSLUCENCY, LOW PAPP A
What is the quadruple test for? When is it offered?
Screening for trisomy 21, Offered from 14-20 weeks
What is in the quadruple test?
a-Fetoprotein - low
b-hCG - high
Unconjugated Oestriol - low
Inhibin A - high
Mnemonic to remember trisomy’s screened for in prengnancy
trisomy 13
patau
trisomy 18
edward
trisomy 21
down’s
What further test may be offered if a pregnancy is deemed as being at high risk of trisomy 21 upon screening?
Chorionic Villous Sampling
Offered at 11-15 weeks
Associated with a small risk of miscarriage
Amniocentesis
Offered at over 15 weeks
Associated with small risk of miscarriage
Cell Free Foetal DNA
Not associated with any risk of foetal harm as it involves taking a peripheral blood sample from the mother
When is chorionic villus sampling offered to test for down’s?
Offered at 11-15 weeks, If a pregnancy is deemed as being at high risk of trisomy 21 upon screening
NIOTE: Associated with a small risk of miscarriage
When is amniocentesis offered to test for down’s?
Offered at over 15 weeks, If a pregnancy is deemed as being at high risk of trisomy 21 upon screening
NIOTE: Associated with a small risk of miscarriage
What test can be done to test for down’s that offers no risk to foetus? Why?
Cell Free Foetal DNA
Not associated with any risk of foetal harm as it involves taking a peripheral blood sample from the mother
When are those with SLE advised to get pregnant?
after their disease has been inactive and stable on treatment for over 6 months
Effect of pregnancy on SLE
no increased risk of flares
Effect of SLE on mother in pregnancy
Increased risk of miscarriage
Increased risk of pre-eclampsia
Effect of SLE on foetus in pregnancy
Increased risk of stillbirth
Increased risk of IUGR
Increased risk of preterm delivery
Neonatal lupus syndrome
Congenital heart block
SLE medications that are safe for conception in pregnancy
Safe: Hydroxychloroquine, Azathioprine
SLE medications that are unsafe for conception i pregnancy
Ensure good disease control prior to conception (aiming for at least 6 months without flares before attempting to conceive)
Baseline investigations for SLE in pregnancy
Renal Function (lupus nephritis is particularly strongly associated with poor pregnancy outcomes)
Anti-dsDNA
Blood Pressure
Quantification of Proteinuria
Anti-Ro and Anti-La antibodies (associated with congenital heart block)
What medication is reccomended for SLE in pregnancy? Why
Recommend aspirin from 12 weeks’ onwards to reduce the risk of pre-eclampsia
What are mothers with SLE in pregnancy at increased risk of? How do we treat this?
Pre-eclampsia, reccomend aspirin from 12 weeks onwards
What additional scans to offer for SLE in pregnancy?
Offer growth scans at 28, 32 and 36 weeks’ gestation
