T2 L19 Pregnancy and diabetes

Question 1

What does diagnosing maternal hyperglycaemia help prevent?

Answer 1

Morbidity in the offspring
An exacerbation of the obesity and type 2 diabetes epidemic
Future type 2 diabetes in the mother

Question 2

What are the 2 groups of women with respect to glucose tolerance?

Answer 2

Those with normal glucose tolerance
Those with abnormal glucose tolerance
- known diabetes or impaired glucose tolerance
- unknown diabetes of impaired glucose tolerance

Question 3

What is gestational diabetes according to WHO?

Answer 3

Any newly found abnormal glucose tolerance test after 1st trimester

Diabetes of impaired glucose tolerance:

• fasting glucose ≥5.6mmol/l
• 2 hour GTT glucose ≥7.8mmol/l

Question 4

What is the IADPSG criteria?

Answer 4

75g glucose tolerance test:

• fasting 5.1mmol/l
• 1 hour 10.0mmol/l
• 2 hours 8.5mmol/l

Diagnose if ≥1 is abnormal

Question 5

Describe what happens in the normal stages of pregnancy

Answer 5

1st trimester:
- organogenesis

2nd trimester:
- further complex development and linkage

3rd trimester:
- accelerated growth

Question 6

Describe maternal metabolism in early pregnancy

Answer 6

Facilitated anabolism
Increased insulin sensitivity
Glucose concentration is slightly lower
Increased maternal energy stores

Question 7

Describe maternal metabolism in later pregnancy

Answer 7

Facilitated catabolism
Increased insulin resistance
Increased transplacental passage of nutrients leading to rapid foetal growth

Question 8

What are the effects of maternal hyperglycaemia in the first trimester?

Answer 8

Increased foetal abnormalities
- fuel mediated teratogenesis

Abnormal placental programming

• increased risk of pre-eclampsia
• excessive glucose transport

Question 9

Give examples of some foetal anomalies caused by maternal hyperglycaemia that occur in the first trimester

Answer 9

Hydrocephalus
Meningomyelocele 
Congenital cyanotic heart disease
Single ventricle and sacral dysgenesis 
Renal agenesis

Question 10

What are the effects of maternal hyperglycaemia in the 3rd trimester?

Answer 10

Excessive fat deposition
Pre-eclampsia
Adverse foetal programming (epigenetics)

Question 11

How can we prevent foetal malformation in hyperglycaemia of pregnancy?

Answer 11

Good diabetes control in 1st trimester - pre-pregnancy counselling
Folic acid
Aspirin
Identify unknown cases of diabetes

Question 12

What can macrosomia lead to?

Answer 12

Difficult birth - shoulder dystocia
Breathing problems
Jaundice
Hypoglycaemia

Question 13

What are some lifetime effects of hyperglycaemia on the foetus?

Answer 13

Obesity
Insulin resistance
Type 2 diabetes
Dyslipidaemia
Hypertension
Vascular disease

Question 14

What women should we be screening?

Answer 14

Previous GDM
Obesity
Family history
High risk racial group
Older age
PCOS

Question 15

What is the treatment of pregnancy hyperglycaemia?

Answer 15

Good maternal glucose 
Appropriate nutrition
Reasonable exercise
Ultrasound monitoring of foetal abdominal girth
Maternal observation of foetal movements

Question 16

What are the targets when treating pregnancy hyperglycaemia?

Answer 16

Fasting glucose <5.1mmol/l
1 hour postprandial glucose <7mmol/l
Foetal abdominal girth <70th centile

Question 17

What drug treatment can be used for gestational diabetes?

Answer 17

Metformin
Basal insulin
Basal bolus insulin
Glibenclamide

Question 18

How should we manage diabetes postpartum?

Answer 18

Maintain good glycemic control
Advice regarding next pregnancy
Contraception advice
Encourage long-term glycemic control
Encourage breast feeding
Screen for diabetes at 12 weeks postpartum
Annual glucose screening

Question 19

What contraception advice should be given postpartum?

Answer 19

Progestogen only pill
Combined OCP after 6 weeks
Mirena intrauterine system
Sterilisation / vasectomy

Question 20

Why should we encourage breast feeding for gestational diabetes?

Answer 20

Child: any breastfeeding will reduce risk by 30-50%
Mother: reduces postpartum weight gain