GESTATIONAL DIABETES

Question 1

physiology of gestational diabetes

Answer 1

1. insulin requirement rise by 30%
2. higher insulin resistance
3. if borderline pancreatic reserve - unable to produce more insulin
4. hypergylcaemia
5. PC with polydipsia and polyuria

Question 2

RF

Answer 2

1. High BMI (>30)
2. previous gestational diabetes/ macrosomic baby
3. PCOS

Question 3

Foetal comp

Answer 3

In pregnancy, glucose is transported across the placenta, but insulin is not.

This can cause fetal hyperglycaemia

if there is a high level of glucose in the maternal circulation. Subsequently, the fetus will increase its own insulin levels to compensate; hyperinsulinaemia.

Insulin is a hormone that has a similar structure to growth promotors, and it therefore causes:

1. Macrosomia – this can cause complications during labour, such as shoulder dystocia, obstructed/delayed labour, and/or higher rates of instrumental deliveries.
2. Organomegaly (particularly cardiomegaly)
3. Erythropoiesis (resulting in polycythaemia)
   Polyhydramnios
   Increased rates of pre-term delivery

Question 4

Post delivery

Answer 4

After delivery, the fetus still has high insulin levels, but no longer receives glucose from its mother. This results in an increased risk of hypoglycaemia – and therefore regular feeding is important.

Additionally, high insulin can cause a reduction in pulmonary phospholipids, which in turn decreases fetal surfactant production. Surfactant acts to reduce the surface tension in alveoli (thus aiding gas exchange), and these babies are at risk of transient tachypnoea of the newborn.

Question 5

Mx

Answer 5

1. lifestyle advice
2. take capillary glucose 4 times a day
3. metformin
4. Insulin of fasting glucose if > 7
5. cap glucose measurements 4 times a day
6. delivery att 37-38 weeks

Question 6

Post delivery

Answer 6

1. 6 weeks - fasting glucose tolerance test

Question 7

pre existing diabetes

Answer 7

asprin from 12 weeks to prevent pre eclampsia