Gestational Diabetes

Question 1

Why does gestational diabetes develop during pregnancy?

Answer 1

Raised progesterone and cortisol

Increased insulin resistance

Increased glucose in a previously non-diabetic woman

Question 2

Risk factors

MACROS mneumonic

Answer 2

Medical or FH of GDM, macrosomia

Age > 40 yrs

Cystic - PCOS

Race - non-white

Obese

Smoking

Question 3

Investigations:

OGTT:

• What does it stand for?
• How is it done? - 3 steps
• Over what levels are classed as GDM?

Answer 3

Oral glucose tolerance test

Check plasma glucose
Give 75mg glucose
Then repeat glucose after 2 hrs

> 5.6 mmol/L FASTING
OR
7.8 mmol/L AT 2 HRS

Question 4

Investigations:

Who should be investigated?

At what gestations are tests done? - 2

Answer 4

Past history of GDM
BMI > 40

18 wks
28 wks

Question 5

Management - Antenatal:

If fasting glucose is 5.6-6.9, what should be tried first?

If fasting glucose is >7, what meds should be started?

What is used to monitor the growth of the baby due to risks of macrosomia?

Answer 5

1st - Diet and exercise
2nd - Metformin
3rd - Insulin if still uncontrolled

Immediate insulin +/- metformin

Growth scans from 28 wks

Question 6

Management - Delivery:

When should delivery be offered for?

What if the mother wants to wait for spontaneous labour?

Macrosomic babies need a c-section. What drug should be given before to prepare the baby?

How often should glucose be monitored during labour?

What is used to maintain glucose levels?

When is treatment stopped?

Answer 6

37 wks - induction or c-section

Fetal monitoring every wk

Steroids

Hourly

Dextrose and insulin infusion

After delivery

Question 7

Complications:

Antepartum?

Peripartum (labour)?

What % of GDM women go on to develop T2DM?

Is GDM likely to recur in future?

Answer 7

HTN
PET

Need for c-section, instrumentation, and tears
PPH

50%

Yes!!!

Question 8

Complications:

Fetal:

• Main ones
• Why do you get neonatal hypoglycaemia with GDM? What can be done to combat it?
• Why might the baby look yellow?

Answer 8

Macrosomia
Shoulder dystocia

This is the result of glucose passing through the placenta, elevating the glucose levels in the fetus, and ultimately increasing the amount of insulin secretion.

Feeding within 30 minutes - check glycose within 2 hrs (or earlier if there are signs)

Increased chance of neonatal jaundice with GDM mothers