Antenatal care Flashcards
Gravidity
How many times a woman has been pregnant
Includes ectopics etc
Parity
How many babies have been delivered at 24+ weeks
Primigravid
First ever pregnancy
Nulliparous
No delivery of a baby >24 weeks
Multiparous
1+ Babies delivered >24 weeks
1st trimester
1-12 weeks
2nd trimester
13-27 weeks
3rd trimester
28wks- delivery
What happens at the booking visit?
Obstetric Hx BP, Urinalysis, BMI Antenatal screening Place of birth Advice Access to services
When is the booking visit
8-12 weeks ideally <10
When is the early dating scan and what happens
10-13+6
Confirms dates, Excludes multiple pregnancy
What is the combined test?
11-13+6 usually at dating scan Nuchal translucency HCG PAPP-A Detects 85%- Trisomies
What results in the combined test would suggest Down’s syndrome?
What about the quadruple test?
High HCG
Low PAPP-A <1
Nuchal translucency >3.5mm
Low AFP, Low oestriol, inc Inhibin-A
Apart from Down’s what else can thickened NT suggest?
Abdominal defect
Cardiac defect
What happens at the Anomaly/Anatomy scan?
18-20+6 Quadruple test PLACENTAL LOCATION Assess gestational age Anatomic survey
What is the Quadruple test
14-17 weeks but up to 20 weeks
AFP, HCG,Oestriol, Inhibin A
75% detection 4.1% false +ves
From the quadruple or combined test what risk is defined as high risk?
What do you do?
1/150 or more
CVS or amniocentesis
What is CVS?
Chorionic villous sampling
11-14 weeks
Miscarriage rate 1-2%
LA,Large needle
What is amniocentesis?
15+ weeks
Miscarriage rate 0.5-1%
Thin needle +/- LA
How do you diagnose Downs/Trisomies antenatally?
CVS/Amniocentesis
What is the IONA screen?
99% sensitivity for Down’s
Detects free-foetal DNA in maternal circulation
Still need amnio for Dx
How do you calculate gestational age in the dating scan?
Crown rump length (mm)
When can you see foetal heart activity?
6-7 weeks
What happens at fetal wellbeing/growth scans?
Estimate foetal weight and plot (Biparietal diameter, Head circumference, Abd circumference, Femur length)
Amniotic fluid index- Sum of deepest verticle pools
Doppler studies- EDF, MCA, Pulsatile index
If high risk have these regularly
Minor problems in 1st trimester?
N+V- resolution likely 16-20wks
Urinary symptoms as GFR inc (Dec Cr and urea)
constipation (decreases with gestation)
Minor problems in 3rd trimester?
Obstetric cholestasis Acute fatty liver of pregnancy Reflux Stress incontinence Varicose veins (inc with gestation) Backache/sciatica Haemorrhoids
Normal Vaginal discharge in pregnancy?
Increased vaginal and cercival blood flow results in whit/clear muccoid discharge
Infection= Offensive, coloured, Itchy
RoM- Watery + profuse
Thresholds for giving oral iron for anaemia antenatally?
1st Tm < 110g/l
2nd TM <105g/l
3rd TM <100g/l
How do you treat obstetric cholestasis?
Urosdeoxycholic acid for symptoms
Induce at 37 weeks
Weekly LFTS and Vit K supplementation
Key diagnostic features of hyperemesis gravidarum
5% pre-pregnancy Wx loss
Dehydration
Electrolyte imbalance
Exclude UTI, Thyrotoxicosis
Admission criteria for hyperemesis gravidarum
Not tolerating oral fluids and dehydrated
Treatment of hyperemesis gravidarum
Check electrolytes and LFTs
IV fluids
+/- Promethiazine or cyclizine
+/- Ondansetron, Metoclopromide
If prolonged may need vitamin supplementation and high dose corticosteroids
Fetal consequences of hyperemesis gravidarum
Growth restriction
Pre-term
Key risk factors for SGA ‘starved small’
Pre-eclampsia Hx IUGR Multiple pregnancy Maternal medical disorders Drug abuse, smoking
Key risk factors for SGA ‘abnormal small’
Chr, infection, genetics
SGA definition
Newborn birth Wx <10th percentile for gestational age
Estimated foetal Wx <10th percentile for gestational age
IUGR vs SGA
IUGR a subtype of SGA
could be constitutionally small
Investigation of SGA
UA doppler
Pulsatile index
EDF
+/- MCA PI +/- CPR
When would you consider delivery of an SGA baby at 32 weeks?
Absent/Reversed EDF in UA
Would also do 2 weekly scans
What do you want the resistance index and pulsatile index to be?
<1
Suggests easy blood flow getting through in both sys and dias
What would you do if an SGA baby had UA PI>95th centile and +ve EDF
UA doppler 2X weekly
Growth every 2 weeks
Delivery at 37 weeks
If the doppler is normal in an SGA baby when would you consider >34 week deliver
Static growth for 3 weeks or MCA <5th centile
When should you feel foetal movements?
18-20 weeks
Priorities when someone presents with reduced foetal movements? Consider DDx
Rule out IUD- Doppler heart beat and CTG (24+)
Infection- Bloods
IUGR- foetal assessment, 48 hr growth scan
What does amniotic fluid volume tell us about fetal sufficiency?
Sparing effect limits non-central organ blood flow
Good indicator of fetal insufficiency
What is prolonged pregnancy? What investigations are important?
Exceeding 42 weeks from LMP
Daily CTG after 42 weeks, Report any decrease in fetal movements, initial USS for growth and liquor volume
Management of prolonged pregnancy
Estimate EDD as accurately as possible +/- induction if high risk
Stretch and sweep at 41 weeks
IoL at 41-42 weeks
How do you estimate EDD at Booking visit?
LMP +7/7 +9/12
What is PPROM?
Preterm Prelabour RoM <37Wks
Investigations to do if PPROM?
Bloods for infection Sterile Spec exam with HVS, VVS, PH CTG and MSU USS for foetal presentation NO DIGITAL EXAM
Dx- Pooling of amniotic at the back of the vaginal fornix
In PPROM What would suggest chorioamnionitis?
Fever, Abd pain, Purulent discharge,, Temp, Tachycardia (Mat or foetal), Yellow brown discharge on speculum
Management of pregnancy if Chorioamnionitis?
Broad Spec Abx- Oral Eryhtromycin
Dexamethasone or Betamethasone 12mg IM
Deliver
N.B Bleeding risk is increased
Management of PPROM if no chorioamnionitis?
Inform neonatal team
Admit
Abx- Oral Erythro?
Stertoids- Dex or Beta 12mg IM 2x doses 12 hour apart
Tocolytic like Nifedipine to allow time for steroids to work
Deliver at 34 weeks as the risk of chorionaminionitis increases as the pregnancy progresses but the risk of RDS decreases, so a trade-off
What is IUGR and what causes it?
Wx <10th percentile
MOSTLY A FAILURE OF PLACENTA
+ multiple pregnancy, infection, APS, Maternal health, Warfarin, Anticonvulsants, Sickle cell, SMOKING, DRUGS, ALCOHOL
May need to attend consultant antenatal clinics
Difference between dizygotic and monozygotic twinning?
Dizygotic- seperate ova fertilised… No more identical than normal siblings… Dichorionic and Diamniotic
Monozygotic… Identical features… Type depends on timing of division
Why is the timing of the division in monozygotic twins significant?
EARLIER= BETTER
Day 0-3 Dichorionic Diamniotic… Division is before implantation so better
Day 4-8 Monochorionic Diamniotic
Day 8-13- Monochorionic Monoamniotic HIGHEST RISK
Principles of management in Multiple pregnancy
Early Dx and consultant led
High dose folic acid and iron
75mg daily aspirin as 5x more likely to get pre-eclampsia
Extra growth scans
Delivery of Dichorionic twins
38 weeks
Planned
Delivery of MCDA and MCMA
MCDA- 36-37 Weeks
MCMA- Elective C-section 32 weeks + 2 weekly USS
Main complication of MCMA
Twin-Twin Transfusion Syndrome
Recipient- Polycythaemia, HTN, Cardiac Hypertrophy, Oedema (Hydrops), Polyhydramnios
Donor- Anaemia, IUGR, Hypotension, Oligohydramnios
Can ablate anastamoses via laser
Complications of Multiple pregnancy
LOTS FOR MOTHER AND BABY
IUGR, Poly, Preterm, abruption, Cord prolapse
Praevia, Placental disease, HTN, PPH
Different types of HTN in Pregnancy
Chronic HTN- Pre-existing and uncommon
Gestational HTN- BP >140/90 after 20 weeks without proteinuria
Pre-eclampsia- BP >140/90 after 20 weeks + >0.3g/24hrs Proteinuria (PCR >30mg/Mol 2+ on dipstick) without UTI
1st line treatment for Gestational HTN
What Anti-HTN should be stopped?
Oral labetolol, Nifedipine if asthmatic
Important to stop Thiazides, ACEi, ARBs because inc congen abnormalities
Target BP for Gestational HTN
<150/90
Note the maternal BP decreases in 1st TM to inc placental Blood flow… hence why its Dx post 20 weeks
How does pre-eclampsia present
Headache, Visual disturbance, Facial oedema, periorbital oedema, Hyper-reflexia, Clonus, Papilloedema, Hepatic capsule engorgement
Monitor for Pul.Oedema and IC haemorrhage
How do you monitor pre-eclampsia
FBC, Cr, LFTs, U+Es (3x week if Sev, 2x if not) USS (Growth, Liquor, Doppler)… Also do a G+S
Measure BP, 4X daily if mild.mod, >4 if Sev
NOT PROTEINURIA
What is mild, Moderate and Severe Pre-eclampsia
Mild >140/90
Mod >150/100
Sev >160/110 OR ALTERED HAEMATOLOGY OR SIG SYMPTOMS
What is HELLP syndrome
Haemolysis
LFTS inc- Rise in Transaminase not ALP (this is raised anyway in pregnancy)
Low Platelets
Management of pre-eclampsia
200mg oral labetolol (Alt= Nifedipine) try 2nd dose then IV if no effect
10mg Oral nifedipine
Mg sulphate until 24 hours post-delivery or last seizure
Hydralazine can be considered
?Steroids
Prophylactic management of pre-eclampsia
75mg Aspirin from 12 weeks if high risk
Who is high risk of pre-eclampsia
Hx pregnancy related HTN, Multiple pregnancy, CKD, SLE, APS, DM, Chronic HTN
Moderate= Fhx, 1st preg, BMI >30, Mat age >30
Principles of delivery in Pre-eclampsia
Timing= 34+ weeks
BP MUST BE CONTROLLED BEFORE C-SECTION
Maternal steroids up to 34 weeks
Repeat scnas
Management of eclampsia
ABC- 02 and intubate
Left lateral position
IV Mg Sulphate
Iv labetolol or Hydralazine
CURE= PLACENTAL DELIVERY
Can be postnatal…
Principles of management for pre-existing DM in pregnancy
Serial growth scans
Induction at 38-40 weeks +/- C section if LGA
BMI>27= must lose weight
5mg folic acid and 75mg aspirin from 12 weeks
Detailed anomaly scan
Stop ACEi and Statins
Monitor BG- Fasting, Pre-meal, 1 hour post meal, Bedtime
Monitor eyes and renal function as function may deteriorate
Diagnosis of Gestational Diabetes
OGTT- 75g oral glucose
2 hour venous plasma glucose >7.8 (or fasting >5.6)
No role for HBA1C
Key RF for GDM?
Who needs screening?
PCOS + Obesity= OGTT at 26 weeks, Previous GDM= OGTT at 16 weeks
Screen- BMI>30, 1st relative with GDM, previous large baby >4kg, High risk ethnicity, Hx still birth (unexplained) Polyhyramnios
Key Principles of management in GDM
Fasting <7mmol/l then trial diet and exercise
If target not met within 1-2 weeks then Metformin
Finally add insulin if needed
What are the complications of GDM?
No increase in Miscarriage or congen abnormalities
Shoulder dystocia, Stillbirth, maternal tears, neonatal hypoglycaemia
Check maternal fasting glucose 6 weeks post-partum for underlying DM
What prophylaxis would someone with a Hx of VTE receive?
Antenatal and 6 week postnatal LMWH
When would you consider antenatal thromboprophylaxis?
Hospital admission, High risk thrombophilia, medical comorbidities, Any surgery, OHSS, Single VTE B/C surgery
(Previous VTE is an absolute indication for antenatal LMWH)
4 or more of what risk factors would make you consider LMWH from 28 weeks?
BMI>30, 35+ yrs, parity >3, Smoker, Varicose veins, Curret pre-eclampsia, Immobility, Low risk thrombophilia, Multiple preg, IVF, FHx unprovoked oes related VTE in 1st degree
What VTE test is useless in pregnancy?
D-Dimer B/C always raised
What are the benefits of VBAC? What are the risks?
Less risk for mum but Increased risk of uterine rupture (0.5% in spont delivery 3% in induced)
75% success inc to 90% if 2nd VBAC
Deliver on labour ward with CTG
Always the risk of an emergency C-section which is higher risk than an elective C-section
Risks of an LCSC
Infection, Bleeding, Adjacent organ injury, scalpel injury to baby, Anaesthesia risk, VTE increased therefore prophylaxis
2nd time the scar tissue is more complex
In the future- Inc rupture risk, adherent placenta, Stillbirth, VD may be higher risk
Safest anti-convulsants in pregnancy
CBZ, Lamotrigine, Levetiracetam
Principles of management in an epileptic pregnant lady?
5mg daily folic acid
Oral Vit K last 4 weeks
Avoid Sodium Valproate, Phenytoin, Phenobarbitone
Managing a UTI in pregnancy
Nitrofuranoin preferred UNLESS 3RD TM
Avoid Trimethoprim in 1st trimester
Dont use tetracyclines as tooth discolouration
Principles of chicken pox management in pregnancy
Check Ab -> Not immune-> IV IG ASAP
Presents within 24 hours of onset of rash? Oral Aciclovir
Analgesia of choice Antenatally?
Paracetamol
NSAIDS inc miscarriage and malformations and premature DA closure
When would you test for anaemia
Booking visit (8-12wks) give if <11g/dl, 28 weeks give if <10.5g/dl
What antibiotic should be avoided in pregnancy?
Co-Amox because of NEC risk to baby
When are the 1st and 2nd doses of Anti-D given?
28 and 34 weeks
IM Anti-D also given after delivery if baby is Rh +VE
Sensitising events in pregnancy?
Amniocentesis, Placental abruption, Trauma, Heavy bleed <12 weeks, Any bleed >12 weeks, EVAC of retained products/Ectopic/Abortion
When do you test for Rh status?
Booking visit
Give at 28 and 34 weeks if Rh -ve and not sensitised
Pathophysiology of Rh status in pregnancy
R-ve mum -> R+ve child with D -antigen-> Leakage of foetal RBC into Maternal circulation -> Anti-D antibody crosses placenta in later pregnancies-> Normocytic anaemia and haemolysis, jaundice in foetus
What does the Anti-D IG do?
Neutralise foetal D-antigen so no maternal Antibodies are created
Indications for high dose (5mg) folic acid
Parent with NTD, or FHx of NTD Antiepileptic drugs Coeliac DM Thalassemia BMI>30
Causes of folic acid deficiency
Methotrexate
Pregnancy
Alcohol excess
Phenytoin
Sequela of folic acid deficiency
Macrocytic megaloblastic anaemia
NTD
What folic acid advice should be given to all women
Pre-conceptual 0.4mg folic acid until 12 weeks gestation
Key points to cover in an antenatal clinic
Movements Previous preg Urinalysis BP Abdo exam Frequency (New-onset?)
Causes of polyhydramanios?
50% Idiopathic Congenital problems in foetus Trisomy Maternal DM Multiple preg Fetal anaemia Hydrops fetalis Substance abuse
What does polyhydramanios increase your risk of?
Prolapsed cord Malpresentation UTIs Preterm PPH
Causes of Oligohydramnios
Either excess loss of fluid or
Decreased foetal urine production
-> RoM, Renal agenesis, renal obstruction, decreased renal perfusion, placental abruption
When is anaemia screened for?
Booking (<11g/Dl) 28 weeks (<10.5g/DL)
What is the ‘dilutional effect’ in pregnancy?
Plasma volume increase is greater than Red cell mass increase
Decreased haematocrit is normal
Normal MCV
Low HB (Normal now ~115g/L)
What Mean corpuscular Hb
MCH= Amount of HB found in RBC
What is Mean Corpuscular Hb concentration?
Concentration of HB in a given volume
What is ferritin
Iron stores
What is Haematocrit
% of Plasma volume that is RBCs ~40%
How does iron deficiency anaemia present on blood results
Microcytic hypochromic anaemia (Decreased MCV, MCH & Dec/Norm MCHC)
How does B12 or folaye deficiency anaemia present on Blood results?
Macrocytic Hypochromic anaemia (Inc MCV, Dec MCH and MCHC)
What tests should you do if there is abnormal Hb on a FBC?
Haematinics (Folate, B12, Ferritin, EPO)
Management of iron deficiency anaemia
100-200mg elemental iron daily
For at least 3 months
+ 6 weeks post partum
Do not take with tea/coffee
Changes to the CV system in pregnancy
Inc HR, inc SV, Inc CO
Inc circulating volume to compensate for blood loss in labour
PVR will be decreased (Hence fainting) but if pathology this will be inc
