Antenatal care Flashcards
what is the rate of congenital rubella syndrome occurring in fetuses when maternal rubella is contracted
- between conception and 11 weeks
- between 12- 16 weeks
- after 20 weeks
Congenital rubella syndrome occurs when maternal rubella is contracted before 20 weeks.
- upto 11 weeks = 90% of fetuses affected
- 12 to 16 weeks = 20% of fetuses affected
- No published case reports of CRS after 20 weeks’
incubation period of rubella
Incubation period 12-23 days (average 14 days)
Symptoms of congenital rubella syndrome
Congenital rubella infection teratogenic with poor prognosis and significant complications (sensorineural deafness, cataracts and cardiac abnormalities most common)
what proportion of pregnancies does Pre-eclampsia effects?
3%
What can be used in high risk patients to lower the risk of pre-eclampsia
Aspirin 75mg OD
Associated with 17% reduction in developing pre-eclampsia when used in at risk groups.
Aspirin mechanism of action
Inhibits cyclooxygenase isoenzymes COX1 and COX2
Blocks the formation of thromboxane A2 n platelets(which promotes platelet aggregation)
Blocks prostacylin formation in endothelial cells (which inhibits platelet aggregation)
Platelets lack a nucleus so cannot upregulate thromboxane production but endothelial cells can. so the overall effect is to inhibit platelet aggregation
NICE advice on Aspirin in Pre-eclampsia
75mg OD from 12 weeks until birth
if more than one moderate risk factor for pre-eclampsia
or one high risk factor for pre-eclampsia
High risk factors for pre-eclampsia
that warrant Aspirin 75mg OD
- hypertensive disease during a previous pregnancy
- chronic kidney disease
- autoimmune disease such as systemic lupus erythematosis or antiphospholipid syndrome
- type 1 or type 2 diabetes
- chronic hypertension
Moderate risk factors for pre-eclampsia
2+ warrant Aspirin 75mg OD
- first pregnancy
- age 40 years or older
- pregnancy interval of more than 10 years
- body mass index (BMI) of 35 kg/m² or more at first visit
- family history of pre-eclampsia
- multiple pregnancy
When is the fetal anomaly scan offered
18-20+6 weeks
what does the fetal anomaly scan screen for?:
- anencephaly
- open spina bifida
- cleft lip
- diaphragamtaic hernia
- gastroschisis
- exomphalos
- serious cardiac abnormalities
- bilateral renal agenesis
- lethal skeletal dysplasia
- Edwards’ syndrome (T18)
- Patau’s syndrome (T13)
Breech complicates what % of term deliveries?
Breech complicates 3-4% of term deliveries
What is External cephalic version?
External cephalic version (ECV) is defined as manipulation of the fetus via the abdomen into a cephalic presentation
Rate of spontaenous version of a breech baby in nulliparous women after 36 weeks
Spontaneous version rates in nulliparous women: 8% after 36 weeks
What is the success rate of ECV?
ECV successful in approximately 50% of cases
40% for nulliparous, and 60% for multiparous
What is the rate of reversion to breech after successful ECV?
Revert to breech after successful ECV <5%
Fetal loss rate for pregnant women with appendicitis
Fetal loss in simple appendicitis is 1.5%
Fetal loss in appendicitis with peritonitis 6%
Fetal loss with perforated appendix 36%
How many weeks on average does a rescue cerclage delay delivery?
Rescue cerclage may delay delivery by 5 weeks.
Also associated with a two-fold reduction in the chance of delivery prior to 34 weeks.
Who should be offered cervical cerclage?
History-indicated cerclage = women with 3+ previous preterm births and/or second-trimester losses
Ultrasound-indicated cerclage = history of mid-trimester loss or preterm birth AND cervical length 25 mm or less before 24 weeks of gestation.
Features of Congenital CMV infection
Sensorineural Hearing Loss Visual Impairment Microcephaly Low Birth weight Seizures Cerebral Palsy Hepatosplenomagaly with jaundice Thrombocytopenia with petechial rash
Diagnosis of fetal CMV infection
Amniocentesis
at least 6 weeks after maternal infection and not until the 21st week of gestation
Management of a pregnancy where fetal CMV confirmed by amniocentesis
Cerebral MRI indicated at 28–32 weeks of gestation.
It may need to be repeated.
Serial ultrasound examination of the fetus every 2-3 weeks until delivery.
What is the most common cause of an acute surgical abdomen in pregnancy?
Appendicitis
Most commonly presents in the second trimester.
Classic presentation of appendicitis in pregnancy
Central abdominal pain that localises to the right iliac fossa.
Associated with fever, nausea, diarrhoea and urinary symptoms.
Management 1st or 2nd trimester Acquisition of Genital Herpes
Initial episode treated acicolvir 400 mg TDS for 5 days
Daily suppressive aciclovir 400 mg TDS from 36 weeks
reduces HSV lesions at term and the need for caesarean section
Does epilepsy carry a risk of teratogenicity?
Epilepsy increases risk of teratogenicity
4% not on medication
6-8% on treatment
All AEDs carry an increased risk of teratogenic effects.
Sodium Valporate has worst teratogenic profile
