2. Principles of antenatal care Flashcards
What medications to avoid in pregnancy?
Retinoid acid – teratogenic
Statins – oligohydramnios
Sodium valproate – neurodevelopmental delay
When is the dating scan?
11-13+6
What happens at the dating scan?
Downs syndrome screening, Nuchal translucency measurement
Risks due to High BMI in pregnancy
Miscarriage, GDM, HTN
Risks due to smoking in pregnancy
IUGR, stillbirth
Daily dose of folic acid?
400 mcg (higher in obesity and epilepsy)
How long to take daily dose of folic acid?
12/40
Risks due to alcohol use in pregnancy?
FAS, learning difficulties, growth restriction
Care in Low Risk pregnancy
Midwife care throughout
Care in High Risk pregnancy
Combined care, monitoring foetal growth (Eg in epilepsy)
OR consultant/hospital only (severe maternal medical disease)
Routine tests in pregnancy
1) Infection: Hep B, HIV, Syphilis (TPHA)
2) Electrophoresis: HbSc Thalassemia
3) FBC: Blood group, screen for red cell antibody
4) Optional: screening for aneuploidy
5) Rubella – eliminated in the UK, not tested for
Down syndrome screening
1st trimester (>90% trisomies detected):
(used in a formula to calculate the risk)
- 1 in 150 risk of aneuploidy prompts an invasive test
2nd trimester (65-70%)
1st trimester Down Syndrome screening
B-HCG, PAPP-A (pregnancy associated plasma protein), nuchal translucency, maternal age
2nd trimester Down Syndrome
B-HCG, Alpha feto-protein, Estriol + inhibin-A
Further invasive testing for Downs Syndrome
- Chorionic Villous Sample
- Amniocentesis
- Maternal serum non-invasive prenatal testing (free foetal DNA)
Chorionic Villous Sample
10-14 weeks
- 100% accurate
- 1% loss rate
- on NHS
Amniocentesis
16-20 weeks
- 100% accurate
- 1% loss rate
- on NHS
Maternal serum non-invasive prenatal testing (free foetal DNA)
- No procedure-related loss
- 99% accurate
- Cost £350
Time of routine anomaly scan
All pregnant women,
18-21 weeks
What happens during the routine anomaly scan?
(18-21 weeks)
- Organs examined: brain, heart, lungs, kidneys, spine, limbs, face
- Placental site is identified
Lethal abnormalities
- Congenital renal agenesis
- Trisomy 18 and 14
- Anencephaly
- Congenital diaphragmatic hernia
- Hypoplastic left heart
Significant abnormalities
- Trisomy 21
- Cleft/lip palate
- Club foot
- Gastroschisis
- Gut atresia
- Cardiac abnormalities
Smoking management in pregnancy
- Nicotine replacement therapy
- Varenicline and Bupropion not licensed for use
When is routine Anti-D prophylaxis given
28 weeks
What are the sensitising events in Rhesus iso-immunization?
Delivery, ante-partum haemorrhage, placental abruption, amniocentesis
Define Rhesus iso-immunization
Mixing of maternal and foetal circulations, mother forms antibodies to foetal RBCs, antibodies can be triggered to attack in the next pregnancy.
When is Breech more common?
In premature deliveries
How to treat breech presentation?
External Cephalic Version - physical manipulation of the baby in the abdomen
Rate of twin pregnancy
1 in 80
Dating scan in Twins
Establish chorionicity (monitor twin to twin transfusion syndrome if monochorionic)
When is routine iron supplementation required?
Twin pregnancies
Rate of stillbirth
1 in 250
Causes of stillbirth
IUGR, placental insufficiency, prematurity, congenital disorders, infection, multiple pregnancy
What is a treatment for Thrush (candida) in pregnancy?
Clotrimazole
Treatment for heartburn in pregnancy
Antacid (gaviscon or magnesium trisilicate)
Treatment for anaemia in pregnancy
Ferrous sulphate
