Antenatal Care

Question 1

Purpose of Antenatal Care

Answer 1

aims to provide Evidence-based Information and Support to make informed
decisions, Advise on Minor problems and symptoms, Assess Maternal and Foetal Risk, Monitor Wellbeing throughout pregnancy
• BP and Urine check at every visit to detect signs of Pre-eclampsia and Diabetes

Question 2

What is shared obstetric care

Answer 2

GP and Community Midwife undertake most Obstetric care, with limited number of visits to Hospital
o Routine Involvement of Obstetrician in care of Uncomplicated Pregnancy does not improve Perinatal Outcomes
o Information given regarding giving birth at home, at Midwife-led unit, or Hospital

Question 3

What happens at first contact?

Answer 3

Folic acid and Lifestyle advice, Antenatal Screening and Booking Appointment

Question 4

When should booking happen?

Answer 4

Booking should happen ideally early in pregnancy (<12/40); Very late bookers, or unbooked pregnancies have higher risk of Perinatal and Maternal Morbidity and Mortality

Question 5

What happens at booking?

Answer 5

should comprise Comprehensive History and Full Physical Examination
o BMI, BP, Dipstick, Ultrasound for Gestational age
o Information on Antenatal Classes, Pregnancy Care Pathway, Nutrition, Diet, Vitamins, Maternity Benefits and information on Foetal development

Question 6

Blood Tests at Pregnancy: FBC

Answer 6

Lower limit of normal Hb at 10.5; Commonest cause of Anaemia is IDA
o Investigate Haematinics (Ferritin, TIBC, Red Cell Folate, Serum B12)

Question 7

Blood Tests at Pregnancy: Blood group and abnormal antibodies

Answer 7

If Rh negative with Rh positive father – Commence Anti D Prophylaxis

Question 8

Blood Tests at Pregnancy: Syphilis

Answer 8

Uncommon but important cause of Neonatal Disease

Question 9

Blood Tests at Pregnancy: Rubella

Answer 9

2% of Nulliparous and 1% of multiparous are non-immune to Rubella; Should
receive Post-Partum Rubella vaccination

Question 10

Blood Tests at Pregnancy: Hep B

Answer 10

Neonates infected are at higher risk of becoming Chronic Carriers
(90%), and higher risk of developing Cirrhosis and HCC
o Neonates given Hep B Vaccination at birth if mother HBsAg positive but e negative; If e positive, +Passive Immunisation (HBIg)

Question 11

Blood Tests at Pregnancy: HIV

Answer 11

Vertical Transmission can be reduced by two thirds if treatment of mother
with Antiretrovirals, and Neonate for 6/52 post; Risk of transmission reduced with C-section and avoidance of Breastfeeding

Question 12

Blood Tests at Pregnancy: Haemoglobinopathies

Answer 12

Hb Electrophoresis – Minor Ethnic or Racial origins with high risk of Haemoglobinopathies
(Mediterranean, Middle Eastern, Indian, SEA for Thalassaemia, African/Afro-Caribbean for
Sickle Cell disease); Also, if Persistent Maternal Anaemia

Question 13

Blood Tests at Pregnancy: Others

Answer 13

Thyroid, HbA1c, Baseline Urea and Creatinine

Question 14

16 week appointment

Answer 14

(Discuss Screening, investigate if Hb<11g/dL, Arrange Anomaly scan at 18-20 weeks)

Question 15

25 weeks

Answer 15

if Primiparous – BP, Urine Drip, SFH plot (The works)

Question 16

28 weeks

Answer 16

Screen Anaemia and Atypical RBC allo-ab, Anti D Prophylaxis, BP, The works

Question 17

31 weeks

Answer 17

The works

Question 18

34 weeks

Answer 18

Discuss Labour and Birth, Anti D Prophylaxis, The works

Question 19

36 weeks

Answer 19

Discuss Breastfeeding, Vit K Prophylaxis, Post-natal care, Mental Health awareness, The works

Question 20

Other antenatal appointments in third trimester

Answer 20

38, 40, 41 weeks: membrane sweep, 42 weeks: induction

Question 21

Prenatal Screening Tests

Answer 21

Prenatal Diagnosis helps in Planning Timing, Mode and Place of Delivery, Preparation for Parents, Planning Specialist Neonatal Services, Foetal Surveillance, In-Utero Treatment and
option of Termination of Pregnancy

Question 22

Screening for chromosomal abnormalities

Answer 22

Negative result doesn’t guarantee no abnormality

Offered to all women at booking

Question 23

Combined Test

Answer 23

For Down Syndrome 
Offered at 11-13 weeks 
Nuchal scan: Increased translucency marker for structural defects
PAPP-A
B-HCG

Question 24

How is Down Syndrome risk calculated?

Answer 24

Down syndrome risk = Maternal Age Risk × Gestation-related risk (NT + Blood tests)
o Foetuses with Downs more likely to have absent/hypoplasia Nasal bone, Significant
Tricuspid Regurgitation

Question 25

Alternative screening for Down's Syndrome

Answer 25

Dating scan plus Triple/Quad Tests at 16/52 – Oestriol, hCG, AFP, and inhibin A o Oestriol reduced in Trisomy 21 and 18; hCG reduced in T18 and raised in T21 o Recommended if NT scan was not possible, or missed window for Combined test

Question 26

Other trisomy screening

Answer 26

Integrated Test (NT and PAPP-A at 10 – 13 weeks, Quad serum at 15 weeks) and Serum Integrated Test (Dating Scan, PAPP-A at 10 weeks, Quad serum at 15 weeks) • AFP – If above 2.2 multiples of median, screening for Open NTDs and other structural defects e.g. Abdominal Wall, Nephrosis, Bowel Obstruction, Teratomas etc o Marker of Adverse Perinatal Outcomes – Foetal death, IUGR, Late Bleeding and Prem

Question 27

Screening for structural abnormalities

Answer 27

Occurs at 18 – 21 weeks Gestation; High pickup rate of CNS but lower of Cardiac defects • Covers Skull Shape and Internal Structures, Spine, Abdominal Shape and Contents, Arms, Legs, Heart, Face and Lips

Question 28

Neural Tube Defects

Answer 28

Occur early in development due to failure of closure; Believed to be reduced due to Folate supplementation; Spinal Bifida and Anencephaly make up 95% of defects o Anencephaly – Absence of Skull vault and Cortex; Incompatible with life o Spinal Bifida – Occulta, Meningocoele, Myelomeningocoele

Question 29

Cardiac Defects

Answer 29

Most common major malformations; May be associated with Chromosomal abnormalities (Commonly T21 and 18); Most common is VSD o Risk Factors – FH, Maternal Rx (Li, AEDs), Maternal DM, Other congenital abnormalities, Increased NT

Question 30

Renal Agenesis

Answer 30

Lethal due to Anhydramnios causing Lung Hypoplasia; May not be evident before 16/40 as Amniotic fluid not fully urinary before then

Question 31

Posterior Urethral Valve Syndrome

Answer 31

(Males, Outflow Obstruction), Hydronephrosis (75% of | Renal Abnormalities; May be PUJ obstruction, VUR, Ureterocoele, PUV)

Question 32

Lung Hypoplasia

Answer 32

Often Oligohydroamnios; Also, Compression; Severity associated with PPROM<25/40, Severe Oligohydramnios, Early delivery; High Mortality

Question 33

Diaphragmatic Hernia

Answer 33

30% incidence of Aneuploidy; 40% Postnatal death from Lung Hypoplasia; Others might require Postnatal Surgery; Foetal surgical techniques in development e.g. Foetoscopic Tracheal Occlusion

Question 34

Congenital Cystic Adenomatoid Malformation

Answer 34

Rare; Normal lung replaced by Proliferation of | Cysts resembling Bronchioles

Question 35

Exomphalos (Omphacocele)

Answer 35

Failure of gut to return to Abdominal Cavity after normal Extrusion and Rotation; Viscera contained within sac, and Umbilical cord arises from apex o 1/3 occur with Chromosomal abnormalities; another 1/3 have other malformations o Prognosis depends on Karyotype, Concurrent malformations, Ischaemia; 40% Mort

Question 36

Gastroschisis

Answer 36

Protrusion of gut through Anterior Abdominal wall defect (usually Right of Umbilicus); Not covered by sac o Usually occurs in very young mothers (<25yrs); No increased risk of Chromosomal Abnormalities; 5 – 10% may die In-Utero or post-natal, but prognosis is good in the remainder of infants

Question 37

Gastrointestinal Obstruction

Answer 37

Duodenal Atresia | (30% T21), Oesophageal Atresia (15% have Aneuploidy), Other Atresias may occur with Syndromes or Gastroschisis

Question 38

Chorionic Villus Sampling

Answer 38

Performed 10-13/40; Aspiration of some Trophoblastic cells Small amount of tissue taken Transabdominally (sometimes Transcervical) under USS guidance for Karyotyping; Rapid analysis is possible with FISH and PCR

Question 39

Chorionic Villus Sampling: Indication

Answer 39

Indications include Karyotyping in first trimester if screening indicates high risk for Aneuploidy, and DNA analysis of parents of carriers of identifiable gene mutation

Question 40

Chorionic Villus Sampling: Risk

Answer 40

Allows for first trimester TOP risk of Miscarriage 1%; Increased risk of Vertical transmission of Blood-borne Viruses

Question 41

Chorionic Villus Sampling: Accuracy

Answer 41

Placental Mosaicism and Maternal contamination can cause misleading results

Question 42

Amniocentesis

Answer 42

Performed >15/40; Aspiration of Amniotic fluid, which contains shed Foetal cells from skin and GI tract; Transabdominal under USS guidance

Question 43

Amniocentesis: Indications

Answer 43

Same indications as CVS, plus allow for Enzyme assay for IEMs; Can also be used to diagnose Foetal Infections e.g. CMV, Toxoplasmosis

Question 44

Amniocentesis: Risk

Answer 44

Lower procedure-attributed risk vs. CVS; Lower risk of Maternal contamination, or Placental Mosaicism