PACES: Obstetric Monitoring

Question 1

What screening occurs at booking, for those women who choose to have it?

Answer 1

Blood tests: group, RhD status, FBC (anaemia), Hb electrophoresis (SCA/Thal), infection (hep B, HIV, syphilis)

Urine dip + MC&S: proteinuria? Asymptomatic bacteriuria?

Question 2

What supplementation should women be on? (checked at the booking visit)

Answer 2

Folic acid 400 μg OD
Vitamin D 10 μg OP

Question 3

In which patients should folic acid supplementation be increased? What is the dose?

Answer 3

5mg OD
Previous NTD
Sickle cell disease
BMI >30
Diabetic
Either parent has NTD
On Anti-epileptics

Question 4

When is the dating scan, and what can it screen for?

Answer 4

11+2 - 14+1w

Viability
Gestation
Multiple pregnancy (+ chorionicity)
Nuchal translucency

Question 5

What are the 3 elements of the ‘triple test’?

Answer 5

USS (for nuchal translucency)
Blood test for B-hCG + PAPP-A

Question 6

What combined test result suggests Downs syndrome?

Answer 6

High NT
High B-hCG
Low PAPP-A

Question 7

What combined test result suggests Edwards or Patau syndrome?

Answer 7

High NT
Low B-hGC
Low PAPP-A

Question 8

During which weeks of gestation can the combined test be carried out?

Answer 8

11+0 - 13+6

Question 9

When is NIPT offered on the NHS?

Answer 9

If combined or quadruple test indicate high risk >1/150

Question 10

What does NIPT analyse?

Answer 10

Small DNA fragments circulating in blood of pregnant woman (cell free fetal DNA, cffDNA)

cffDNA derives from placental cells + is usually identical to fetal DNA

Sensitivity + specificity are very high for trisomy 21 (>99%) + similarly high for other chromosomal abnormalities

Question 11

What diagnostic tests can confirm Down syndrome? When is each used?

Answer 11

Chorionic Villous Sampling: 10-15w
Amniocentesis: 15-20w

Question 12

What can be offered if a woman books late and misses the opportunity for a combined test?

Answer 12

Quadruple test (used to be Triple)

Question 13

What are the components measured in the quadruple test?

Answer 13

Alpha-fetoprotein (AFP)
Total human chorionic gonadotophin (hCG)
Unconjugated oestriol (uE3)
Inhibin-A (inhibin)

Question 14

What results of the quadruple test indicate Down syndrome?

Answer 14

AFP: LOW
hCG: HIGH
Inhibin: HIGH
Oestradiol: LOW

Question 15

What results of the quadruple test indicate Edward’s syndrome?

Answer 15

AFP: LOW
hCG: LOW
Inhibin: Normal
Oestradiol: LOW

Question 16

What results of the quadruple test indicate Neural Tube defects?

Answer 16

AFP: HIGH
hCG: Normal
Inhibin: Normal
Oestradiol: Normal

Question 17

At how many weeks is the anomaly scan?

Answer 17

18-20w

Question 18

What is looked for on the anomaly scan?

Answer 18

Structural anomalies
Placental location
Amniotic liquor volume
Gender + growth of foetus

Question 19

If the placenta is low at the anomaly scan, when should a repeat scan be offered?

Answer 19

32w

Question 20

Which vaccines are offered during pregnancy and when?

Answer 20

Flu vaccine: Anytime September-January (e.g. booking)
Pertussis: 16-32w
COVID: Anytime

Question 21

When is the first GP review during pregnancy, and which women should attend?

Answer 21

25w: only nulliparous
Measure SFH
Discuss baby’s movements + any concerns

Question 22

When is the OGTT if indicated?

Answer 22

ASAP after booking if previous GDM
If high risk: 24-28w

Question 23

When is anti-D prophylaxis given to women who are RhD negative?

Answer 23

28w
34w

Question 24

At how many weeks gestation is ECV offered to women with an uncomplicated singleton breech pregnancy?

Answer 24

36w in Primip
37 in Multip

Question 25

Recall the frequency and start date of serial growth scans in mothers with pre-existing hypertension

Answer 25

Scans at 28w, 32w + 36w

Question 26

How often is BP measured in mothers with pre-existing hypertension?

Answer 26

Weekly if poorly-controlled Every 2-4w if well-controlled

Question 27

Recall the timeline of BP monitoring post-partum in mothers with pre-existing hypertension

Answer 27

Day 1 Day 2 Once on day 3-5 F/U with GP at 2w

Question 28

What extra scans are done in women with CMV infection?

Answer 28

USS every 2w from dx Foetal MRI at 28w

Question 29

What extra scans do women with pre-existing gestational diabetes mellitus have?

Answer 29

Foetal cardiac scan at 20w Serial growth scans at 28w, 32w and 36w

Question 30

Recall the timeline of screening for complications of diabetes mellitus in women with pre-existing diabetes?

Answer 30

Retinal + renal screening at booking If abnormal: repeat at 16w If normal: repeat at 28w

Question 31

What extra visits will mothers with epilepsy have?

Answer 31

Obs med clinic every 2w Serial growth scans at 28w, 32w and 36w

Question 32

In severe gestational hypertension (BP >160/110), how often should BP be measured on the ward?

Answer 32

Every 15-30 mins

Question 33

How often should a urine dip be performed in gestational hypertension?

Answer 33

Once or twice a week in moderate HTN Daily whilst admitted

Question 34

What extra blood tests are done in gestational hypertension?

Answer 34

Weekly FBC, LFT and U&E

Question 35

What extra scans do women with gestational hypertension have?

Answer 35

US foetal surveillance every 2w

Question 36

Recall the timeline of obs med appointments for women with pre-existing cardiac disease

Answer 36

Every 2w until 24w, weekly thereafter

Question 37

When are maternal echocardiograms performed in women with pre-existing cardiac disease?

Answer 37

1. Booking 2. 28w

Question 38

What extra scans do women with pre-existing cardiac disease have during pregnancy?

Answer 38

Specialist foetal cardiac scan at 22w (nb this is at 20w in pre-existing DM)

Question 39

Recall the extra monitoring given to mothers who are HIV+

Answer 39

Joint obs med clinic every 2w Viral load every 2w, at 36w and delivery

Question 40

Recall all of the extra monitoring offered to women with multiple pregnancies

Answer 40

FBC at 20-24w Regular BP monitoring (increased risk of eclampsia) OGTT at 28w (at higher risk) TTTS monitoring/ growth scans: - every 2w starting at 16w for MCDA twins - every 4w starting at 20w for DCDA twins

Question 41

What extra monitoring is done in obstetric cholestasis?

Answer 41

Weekly LFTs Doppler and CTG every 2w

Question 42

Recall the timeline of scans in suspected placenta praevia

Answer 42

If detected at 20w, rescan at 32w If still low, rescan at 36w If still low at 36w, offer C section

Question 43

Recall the schedule of extra monitoring in PPROM

Answer 43

Admit until 28w After 28w, monitor 3x/w for signs of chorioamnionitis

Question 44

What extra monitoring is available for mothers whose foetus is SGA?

Answer 44

SFH at booking + at every antenatal appointment (for everyone) If appears SGA, confirm with foetal biometry at 20w If confirmed SGA, do uterine artery doppler at 20-24w If abnormal, serial scans weekly from 26w onwards

Question 45

Recall the timeline of TFTs in women with pre-existing thyroid disease in pregnancy

Answer 45

Every 2 weeks at obs med clinic to ensure euthyroidism Postnatally, 6w check with GP

Question 46

When are women screened for anaemia and red cell autoantibodies in pregnancy?

Answer 46

Booking 8-12w 28w

Question 47

At what thresholds should women be given iron for anaemia in pregnancy?

Answer 47

First trim: <110 2nd + 3rd trim: <105 Post partum: <100