Antenatal care Flashcards
What should women be informed about the additional risk of miscarriage following amniocentesis or CVS?
It is likely to be below 0.5%
What is the earliest gestation amniocentesis should be performed?
15 weeks gestation
What is the earliest gestation CVS should be performed?
10 weeks gestation
What should women be informed about the additional miscarriage risk for twin pregnancy following amniocentesis or CVS?
The additional risk is around 1%
What gestation is CVS usually performed between?
11+0 and 13+6 weeks gestation
1-2% of all CVS results will be affected by which confounding complication?
Combined placental mosaicism
RCOG recommends those trained in CVS and Amniocentesis should carry out how many of these procedure per year as a minimum to maintain skills?
20
Aside from miscarriage, what other risk is increased if amniocentesis is carried out prior to 15 weeks gestation?
Talipes equinovarus
What risks are increased with CVS before 10 weeks?
Oromandibular and limb defects
What complication is increased when amniocentesis is carried out in the third trimester?
Culture failure
Corticosteroids should be offered to women between which gestations when imminent preterm birth is anticipated?
24+0 - 34+6 weeks
What are the two potential harmful side effects of antenatal corticosteroids for the neonate?
Neonatal hypoglycaemia and developmental delay
What is the number needed to treat to prevent 1 neonatal death by giving antenatal corticosteroids between 22-34+6 weeks gestation?
38.5
How should women with multiple pregnancy be counselled about the use of antenatal corticosteroids?
In line with the guidance for singleton pregnancy, however they should be advised of the uncertainties around their use in multiple pregnancy
What is the median latency of delivery after PPROM ?
7 days
What is the change in blood oxygen saturation during a flight at cruising altitude?
SpO2 reduced by 10%
What does the evidence show about risk of adverse pregnancy events with air travel?
There is no good data to suggest an increase in preterm labour, PPROM or abruption
What advice should be given to women about the maximum gestation to fly at?
36 weeks if no complications
32 weeks if any risk factors for preterm birth
Which conditions are absolute contraindications to air flight?
Anaemia with Hb <75
Recent haemorrhage
Otitis media or sinusitis
Serious cardiac or respiratory disease
Recent sickle cell crisis
Recent GI surgery
A fracture
What advice should be given to pregnant women about antimalarial therapy?
Anti-malarials are safe in pregnancy
Which travel vaccines should be avoided in pregnant women?
Live vaccines such as the Yellow Fever vaccine
What percentage of babies born in the UK weigh more than 4,000g?
10%
What is the Number Needed to Treat to prevent 1 fracture by using IOL in LGA?
60
Antepartum haemorrhage is defined as vaginal bleeding after what gestation?
24 weeks
APH complicates what percentage of all pregnancies?
3-5%
What is the definition of minor APH?
Blood loss less than 50mls which has settled
What is the definition of major APH?
Blood loss of 50-1,000mls with no signs of clinical shock
What is the definition of massive APH?
Blood loss greater than 1,000mls and or signs of clinical shock
What is the incidence of recurrent placental abruption?
4.4%
What is the relative risk of placental abruption for women who have first trimester bleeding with an intrauterine haematoma?
Relative Risk 5.6
What is the recurrence rate of placental abruption in women who have had two previous pregnancies complicated by abruption?
19-25%
Approximately what percentage of placental abruptions happen in “low risk” women?
70%
What should be avoided in placenta praevia?
Vaginal and rectal examinations
Penetrative sexual intercourse
What neonatal outcomes are associated with unexplained APH?
Increased risk of preterm birth
Increased rates of IOL
Increased neonatal admission
Increased rates of neonatal hyperbilirubinaema
Decreased birth weight
What should be considered in cases of APH associated with rupture of membranes?
Vasa praevia
What investigation should be performed for Rhesus negative women presenting with APH?
Kleihauer
What is the sensitivity of ultrasound in identifying placental abruption?
24%
Antenatal corticosteroids are associated with a reduction in the risk of… (3)
- Neonatal death
- Respiratory distress syndrome
- Intraventricular haemorrhage
How should antenatal care be changed in a low risk woman with APH from placental abruption or unexplained cause?
- The pregnancy should be reclassified as high risk
- Serial fetal growth scans should be performed
What action should be considered in active APH after 37 weeks?
IOL should be considered to avoid the risk of placental abruption
What advice should be given about fetal monitoring for women with APH?
Women with one episode of minor APH with no subsequent concerns about maternal or fetal wellbeing could have intermittent auscultation
Women with major or recurrent minor APH and those women with suspected abruption should have CEFM
What postnatal plan should be put in place for women with APH?
Recommend active management of the third stage
How should anti-D be managed in Rh negative women with APH after 20 weeks?
500 units Anti-D should be given followed by Kleihauer - if >4mls leak then further anti-D is indicated
Serum lactate above which threshold is indicative of tissue hypoperfusion?
> =4mmol/l
What are the two most common pathogens identified in pregnant women dying of sepsis?
Group A Strep and E.coli
What are the drawbacks of using Co-Amoxiclav to treat maternal sepsis?
- Does not cover MRSA or Pseudomonas
- May cause necrotising enterocolitis in the neonate
When should haemoglobin be rechecked after initiating treatment for anaemia?
After 2 weeks
When should pregnant women be screened for anaemia?
At booking and at 28 weeks
Women with multiple pregnancy should have an additional FBC at 20-24 weeks
How often should women at high risk of needing blood transfusion (e.g. placenta praevia/accreta) have Group and Screen samples sent?
At least weekly
What dose of Anti-D should be given to Rhesus negative women who receive autologous cell salvage blood?
1,500 units
How often should FFP be transfused during major obstetric haemorrhage?
1 unit FFP should be transfused for every 6 units of Red Blood Cells
When is Cryoprecipitate indicated in major obstetric haemorrhage?
- Give the first dose of 2 5-unit pools early
- Give subsequent Cryoprecipitate to keep Fibrinogen levels above 1.5g/l
What platelet level should trigger platelet infusion in major obstetric haemorrhage?
75 x 10^9
What percentage of direct maternal deaths in the UK is caused by haemorrhage?
10%
Which vitamin are obese women at high risk of being deficient in?
Vitamin D
Above what BMI should women have a review for anaesthetic assessment in pregnancy?
> 40
What is the guidance on assessment for GDM in women with obesity?
All women with BMI >30 should have a GTT
Above what BMI should serial growth scans be offered due to reduced utility of SFH?
> 35
Above what depth of subcutaneous fat should women have the subcutaneous tissue space closed at Caesarean section?
2cm
What are the BMI thresholds for class I, II and III obesity?
Class I 30-34.99
Class II 35-39.99
Class III >40.00
What are pregnant women with obesity at increased risk of during pregnancy? (12 in total)
- Miscarriage
- GDM
- Pre-eclampsia
- VTE
- Induced labour
- dysfunctional or prolonged labour
- Caesarean section
- anaesthetic complications
- PPH
- Wound infections
- mortality
- Delayed initiation of breastfeeding
Weight loss between pregnancies reduces which risks?
Stillbirth
Hypertensive complications
Macrosomia
Which congenital malformation can arise in babies born to mothers who use Topiramate in pregnancy?
Cleft lip and palette
What is the relative risk of pre-eclampsia in overweight, obese and severely obese women?
1.7
2.93
4.14
(Obese women are 3-4 times more likely to get pre-eclampsia)
What did the FaSTER trial demonstrate with relation to maternal obesity?
Lower sensitivity and higher false negative rate when screening for aneuploidy with ultrasound
What percentage of obese primparous women will have a vaginal birth following IOL?
60%
how many antenatal appointments should low risk nulliparous and parous women have respectively?
Nulliparous women should have 10 antenatal appointments
Parous women should have 7 antenatal appointments
What advice should women be given about sleeping position after 28 weeks?
Women should be advised to avoid sleeping on their back after 28 weeks as this may increase the risk of stillbirth
What advice should be given to women regarding caffeine intake in pregnancy?
Caffeine intake should be limited to 200mg per day to reduce risks of low birth weight in the baby
Constipation affects up to what percentage of pregnancies?
38%
What are the ROME III diagnostic criteria for constipation?
- At least 2 of:
a. straining for >25% of defecations
b. Lumpy or hard stools in at least 25% of defecations
c. Sensation of incomplete emptying for at least 25% of defecations
d. Sensation of anorectal obstruction/blockage for at least 25% of defecations
e. Manual maneouvres to facilitate at least 25% of defecations
- Loose stools are rarely present without the use of laxatives
- Insufficient criteria for irritable bowel syndrome
Which promotility hormone is inhibited by increasing levels of progesterone in pregnancy, leading to constipation?
Motilin
What is the role of the RAAS system in constipation?
Increased RAAS results in sodium and water reabsorption from the gut, reducing stool water content
What is the treatment of choice for chronic constipation in pregnancy?
Polythylene glycol (PEG, an osmotic laxative)
*Movicol is a polymer of PEG
Which laxatives should be avoided in the third trimester and why?
Stimulant laxatives should be avoided as they have been shown to cause uterine contractions
Why should Docusate sodium be avoided in pregnancy?
It can cause neonatal hypomagnesaemia
Which medication can be used in moderate to severe constipation associated with IBS-C and works by increasing c-GMP to decrease visceral pain?
Linaclotide
How does ECV affect the outcome of labour?
Women should be informed that following successful ECV, there is a slightly increased rate of instrumental birth or Caesarean section compared to spontaneous cephalic labour
When should ECV be offered?
- Typically from 37 weeks
- ECV can be offered to nulliparous women from 36 weeks
How does 1 previous Caesarean affect risks of ECV?
The risks of ECV following 1 previous Caesarean are not increased compared to the unscarred uterus
What can be given to improve the success rate of ECV?
Use of tocolysis with betamimetics (Terbutaline) improves the success rate of ECV
Breech presentation complicates what proportion of term deliveries?
3-4%
What is the risk of emergency Caesarean within 24 hours of ECV?
0.5%
How does the risk of fetal mortality compare between vaginal breech, elective Caesarean and vaginal cephalic birth
- Vaginal breech - 2/1,000
- Caesarean - 0.5/1,000
- Vaginal cephalic - 1/1,000
What is the rate of emergency Caesarean section in women planning vaginal breech birth?
40%
Which factors increase the risks of vaginal breech birth (5)
- Hyperextended neck on ultrasound
- EFW >3.8Kg
- EFW <10th centile
- Footling presentation
- Evidence of antenatal fetal compromise
Are induction and augmentation appropriate in vaginal breech birth?
- IOL is not recommended for vaginal breech birth
- Augmentation of slow progress should only be considered if contraction frequency is low in the presence of epidural anaesthesia
How should a first twin in breech position be delivered?
Planned Caesarean section is recommended where the leading twin is breech
How should a second twin in breech position be delivered?
Routine Caesarean section for breech presentation of the second twin is not recommended
What advice should be given about the Varicella vaccine and breastfeeding?
It is safe to breastfeed following Varicella vaccination
How should pregnant women without previous exposure to chickenpox be managed following an exposure to chickenpox or shingles?
She should have a blood test to determine VZV immunity
How should a women not immune to VZV be managed if she has had a significant exposure?
She should have PEP with Aciclovir from day 7 to day 14 post exposure
When is VZIG effective following contact with Chickenpox or shingles?
Up to 10 days following exposure
For what timespan should non-immune pregnant women who have been exposed to chickenpox be considered as potentially infectious?
From day 8-28 if they received VZIG or day 8-21 if they do not receive VZIG
How soon after PEP with Aciclovir or VZIG can another course be prescribed if there is repeat exposure?
Aciclovir can be repeated after 7 days
VZIG can be repeated after 3 weeks
What are the maternal risks of Varicella?
Increased risk of pneumonia, hepatitis and encephalitis
What advice should women with chickenpox be given about avoiding susceptible individuals?
Avoid susceptible individuals until the lesions have crusted over (usually around 5 days)
When should Aciclovir be prescribed for women with Chickenpox?
Within 24 hours of the onset of rash and if they are 20 weeks gestation or beyond
What is the advice about VZIG for women with chickenpox?
VZIG has no therapeutic benefit once the rash has developed
What fetal investigation should be offered for a pregnant woman who develops chicken pox and when should this happen?
Refer to fetal medicine for detailed ultrasound at 16-20 weeks or 5 weeks after infection
Amniocentesis has a good negative predictive value for fetal damage secondary to chickenpox and so should be offered
How should pregnant women be managed following a chickenpox infection in the last 4 weeks of pregnancy?
Avoid planned delivery for at least 7 days following the onset of maternal rash
Inform a neonatologist of all babies born to mothers with chickenpox
What are the characteristics of fetal varicella syndrome?
Skin scarring in a dermatomal distribution
eye defects
Hypoplasia of the limbs
Neurological abnormalities
(can happen following maternal infection up to 28 weeks)
What are the high risk factors for pre-eclampsia?
Previous hypertensive disease in pregnancy
Chronic kidney disease
Autoimmune disease such as SLE or antiphospholipid syndrome
Type 1 or Type 2 diabetes
Chronic hypertension
What are the moderate risk factors for pre-eclampsia?
Nulliparity
Age >=40
Pregnancy interval >10 years
BMI 35 or more at booking
FH pre-eclampsia
Multiple pregnancy
What is the diagnostic threshold for pre-eclampsia using albumin-creatinine ratio
8mg/mmol
What is the range of gestational ages for PLGF testing?
20-36+6 weeks
How often should women with chronic hypertension be seen in ANC?
Weekly if hypertension is poorly controlled
Every 2-4 weeks if hypertension is well controlled
How should BP be monitored postnatally in women with chronic hypertension?
Daily for the first 2 days
At least once between days 3 to 5
Review of antihypertensives at 2 weeks
How often should women with gestational hypertension have BP measured?
Once or twice a week until BP is 135/85 or less
How often should women with severe gestational hypertension have their BP meausred?
Every 15 to 30 minutes until BP is <160/110
How often should urine dip be performed for protein in women with gestational hypertension?
Once to twice per week
How often should urine dip be performed for protein in women with severe gestational hypertension?
Daily while admitted
How often should PET bloods be performed in women with gestational hypertension?
Weekly
How often should fetal growth assessment be performed in women with gestational hypertension?
Every 2-4 weeks
How often should blood pressure be monitored for women with pre-eclampsia?
Every 48 hours as outpatient
At least 4 times daily whilst admitted to hospital
How often should women with pre-eclampsia have their bloods tested?
Twice weekly
3 times per week if severe hypertension
How often should women with pre-eclampsia have fetal growth monitored?
Every 2 weeks
What are the sequelae of pre-eclampsia which should prompt delivery prior to 37 weeks?
Poor BP control despite 3 agents
SpO2 <90%
Progressive deterioration in LFT, renal function or platelet count
Ongoing neurological features
Placental abruption
Reversed end-diastolic flow
What is the name for the thin, continuous fibrinoid layer between anchoring villi and uterine decidual cells?
Nitabuch’s membrane
What is the role of Methotrexate in PAS?
There is no role for Methotrexate in PAS in treatment of retained placental tissue as there are no rapidly dividing cells in the third trimester placenta
What are the clinical criteria for diagnosis of FIGO grade 1 placenta accreta?
No separation with synthetic oxytocin or gentle cord traction
Attempts at manual removal result in heavy bleeding from placental site requiring mechanical or surgical procedures
At laparotomy or caesarean, there is no obvious distension over the placental bed, no neo-vascularity and no placental tissue seen invading through placental surface
What are the clinical criteria for FIGO grade 2 PAS?
Abnormal macroscopic findings over the placental bed such as bluish/purple colouring or distension
Significant amounts of hypervascularity
No placental tissue seen invading through the placental surface
Dimple sign: gentle cord traction results in the uterus being pulled inwards without separation of the placenta
What are the clinical criteria for FIGO grade 3a PAS?
Abnormal macroscopic findings on uterine serosal surface and placental tissue seen invading through the surface of the uterus
No invasion into any other organ - a clear surgical plane can be seen between the bladder and the uterus
What are the clinical criteria for FIGO grade 3b PAS?
Placental villi are seen to be invading into the bladder but no other organs
A clear surgical plane cannot be seen between the bladder and the uterus
Which ultrasonographic features of PAS have been seen in 98% of low-risk pregnancies with normal placentas?
Lacunae
Sub-placental hypervascularity
Irregular bladder wall
Which ultrasonographic features of PAS are rarely seen unless there is PAS or UD?
Placental bulge
Bridging vessels
A myometrium <1mm thick
Loss of the retroplacental clear zone
What is the risk of PAS in a woman with placenta praevia and 1 prior Caesarean?
3%
What is the risk of PAS in a woman with placenta praevia and 2 prior Caesareans?
11%
What is the risk of PAS in a woman with placenta praevia and 3 prior Caesareans?
40%
What is the risk of PAS in a woman with placenta praevia and 4 prior Caesareans?
61%
What was the overall maternal death rate in 2020-2022?
13.56 per 100,000
What was the leading direct cause of maternal death in the most recent MBBRACE report?
Venous Thromboembolism
How much higher are the odds of VTE in pregnant women with cancer?
7 times increased
