Pregnancy Risk Assessment Flashcards
(45 cards)
What features are investigated in a maternity risk assessment during the booking appointment
Gestational diabetes risk
Pre-eclampsia
Foetal growth restriction
Venous thromboembolism
What are the risk factors for a high risk pregnancy
Any previous complicated pregnancies (biggest risk for another abnormal pregnancy)
Maternal factors
- Age <15yo or >35yo
- Pre-pregnancy weight under 45kg or obese
- Height under 5 ft (1.5m)
- Hypothyroid/Hyperthyroid
Gynaecological
- Incompetent cervix
- Uterine malformations
- Small pelvis
- Previous obs hx for recurrent miscarriages
Social
- Being single
- Smoker or alcohol
- Illicit drugs
- No access to early prenatal care
- Low socioeconomic status
What should be done for women with a high risk pregnancy
Refer for obstetrician led care
Continued surveillance - more frequent scans
Consider aspirin, high dose folic acid etc.
Who is given high dose folic acid
Previous child with NTD
Diabetes mellitus
Woman on an anti-epileptic
Obesity (>30 BMI)
HIV positive taking co-trimoxazole
Sickle cell disease
What are the methods of monitoring pregnancy
Cardiotocography
Growth scans
Foetal doppler
Foetal blood sampling
Describe the production of amniotic fluid as the pregnancy progresses
0-12 weeks: Passive transfer of fluid across the amniotic membranes from chorionic cavity
Before 20 weeks: Amniotic fluid isotonic like maternal plasma
19 weeks: Keratinisation of foetal skin AF circulation from foetus
Production: foetal urination, the respiratory tract system, oral secretion and transfer across the cord and placenta
Removal: foetal swallowing, intra-membranous, respiratory fluid
Define oligohydramnios
Decreased volume of amniotic fluid, <5th centile
Deepest pool <2cm
What are the risk factors for oligohydramnios
Reduced input fluid: placental insufficiency, pre-eclampsia
Reduced output fluid: structural pathology (AR PKD), medications (ACEi, NSAIDs)
Lost fluid: ROM, IUGR, post-term pregnancy carry, TTTS
Chromosomal abnormalities
Multiple pregnancy
Infections
What are the signs and symptoms of oligohydramnios
History of fluid leak PV, rupture of membranes – commonly asymptomatic
Abdominal exam – decreased fundal height, foetal parts easily palpable
Speculum – assess for membrane rupture if appropriate
What investigations should be done for oligohydramnios
USS – liquor volume, foetal anomalies
CTG– foetal wellbeing
What is the management for oligohydramnios
Term – delivery is appropriate, IOL if no CI
Pre-term – monitor serial USS for growth, liquor volume, dopplers, regular CTGs, delivery if further abnormalities arise (note: amnioinfusion has a very limited role or effect)
What are the complications of oligohydramnios
Labour – increased incidence of CTG abnormalities, meconium liquor, emergency CS
Neonate – pulmonary hyperplasia, limb deformities
Prognosis – increased perinatal mortality rates with early onset oligohydramnios
Define polyhydramnios
AFI >95th centile, 2-3L fluid
Deepest pool >8cm
What are the risk factors for polyhydramnios
Failure of foetal swallowing:
- Neurological - neurology, chromosomal abnormalities
- GIT - duodenal atresia, oesophageal atresia
Congenital infections
Foetal polyuria: maternal diabetes, TTTS
What are the signs and symptoms of polyhydramnios
Symptoms of underlying cause
Abdomen – increased fundal height, impalpable foetal parts, tense abdo
What investigations should be done for polyhydramnios
Liquor volume, foetal growth, umbilical artery dopplers, exclude foetal anomalies
Other – exclude maternal diabetes
What is the management for polyhydramnios
Antenatal monitoring of foetus, ensure diabetes control, paediatrician present at delivery
Amnioreduction (if gross polyhydramnios + discomfort)
COX inhibitors to decrease foetal urine output
What are the complications and prognosis of polyhydramnios
Pre-term labour (PTL), malpresentation, placental abruption, cord prolapse, PPH, increased risk CS
Prognosis – increased perinatal morbidity and mortality, related to PTL/congenital
What are the types of doppler scan
Umbilical artery
Cerebral circulation: middle cerebral artery
Venous circulation: ductus venosus
What is a sign of foetal compromise in the doppler
severe placental dysfunction: Absent end diastolic flow or reverse end diastolic flow (suggests high resistance circulation) in the UMBILICAL doppler
Compromise: low-resistance pattern in comparison to thoracic aorta or renal vessels (MCA)
Ratio of the pulsatility index (PI) (MCA vs UmbA)
Describe chorionic villi sampling and what is the miscarriage rate
USS-guided needle aspirate of placental tissue
performed 10-13/40 (i.e. week 12)
1% miscarriage rate
Describe amniocentesis and what is the miscarriage rate
USS guided needle, avoid entry of placenta, small aspirate of amniotic fluid
performed ≥15/40
1% miscarriage rate
What supportive management must be done for diagnostic procedures (amniocentesis and CVS)
anti- RHD given to RH-neg women (sensitising event)
What are the indications for diagnostic testing of the foetus
Demonstrated risk at antenatal screening
Suspected foetal anomaly on USS
FHX of inherited disorder
Known carrier status for inherited disorder
Previous pregnancy with chromosomal disorder
Increased maternal age