Obstetrics

Question 1

Aims of a preconception meeting

Answer 1

• health status
• rubella status
• glucose control in diabetics
• Medication review
• 400microg folic acid

Question 2

How is gestational age measured?

Answer 2

crown-rump length if under 14 weeks.

Question 3

Routine booking investigations

Answer 3

urine culture 
FBC 
Antibody screen 
Serological test for syphilis 
Rubella Ig
Offer HIV and HepB
Ultrasound 
Screening for chromosomal abnormalities 
Haemoglobin electrophoresis

Question 4

Who should get the increased dose of folate (5mg)?

Answer 4

BMI >30, diabetes, sickle cell, malabsorption, antiepileptics

Question 5

Who gets vitamin D supplementation?

Answer 5

10microg a day for all women.

25microg a day for BMI >30, south asian or afro-carribean origin, low sunlight exposure, increased pre-eclampsia risk

Question 6

When is the ultrasound for structural abnormalities?

Answer 6

20 weeks

Question 7

HIV pregnancy percentage

Answer 7

0.1-0.5%

Question 8

What is treatment for HIV in pregnancy and what is its effect?

Answer 8

reduces vertical transmission risk from 30-<1%
ART + viral load monitoring
Planned delivery
Infant antiretroviral treatment
Avoidance of breast feeding

Question 9

What is the incidence of Down’s without screening?

Answer 9

1;700

Question 10

What does the combined down’s test measure?

Answer 10

nuchal translucency, Papp-A and HCG, combined with mothers age and babys gestation to give a result.

Question 11

What is the baseline risk of congenital abnormalities?

Answer 11

2%

Question 12

What are the differences between amniocentesis and chorionic villus sampling?

Answer 12

Amniocentesis takes amniotic fluid from 15 weeks (1% risk). CVS is biopsy of trophoblast from 11 weeks (greater risk)

Question 13

Down’s syndrome - inheritance, effect

Answer 13

Usually result of non-dysjunction at meiosis but 6% due to balanced chromosomal translocation in parents. More common with increased maternal age. Mental handicap + characteristic facies + 50% congenital cardiac disease.

Question 14

Other chromosomal abnormalities

Answer 14

• Edwards syndrome (18x3)
• Patau’s syndrome (13x3)
• Klinefelters (XXY)
• Turners (XO)