Post-natal Care
- Insulin requirements fall dramatically after delivery, therefore reduce insulin doses immediately to pre-pregnancy levels, to avoid hypoglycaemia
- Encourage slightly higher blood glucose levels than during pregnancy
- In breast-feeding mothers, reduce insulin dose further once lactation is established
- Discuss contraception while the patient is still in hospital
- All women should be seen by the diabetes pregnancy care team six weeks after delivery
GESTATIONAL DIABETES
Gestational diabetes mellitus (GDM) affects 2-4% of pregnancies and is defined as carbohydrate intolerance of variable severity,
with onset or first recognition in pregnancy. A screening programme for GDM should identify those pregnant women with blood glucose
levels that are associated with an adverse fetal outcome or an increased risk of future diabetes in the mother.
- In normal women during pregnancy, the range for fasting blood glucose is lower than in non-pregnant women
- Glycosuria with normal blood glucose levels is common, due to a lowering of the renal glucose threshold.
Screening for GDM
- Urine should be tested at each antenatal visit for glycosuria (preferably fasting sample)
- Timed laboratory venous plasma glucose measurements should be made
- At booking visit
- At 28 weeks gestation
- In cases when glycosuria 1+ or more is detected
- A 75g oral glucose tolerance test (OGTT) should be performed if the plasma glucose is
- 5.5 mmol/L 2 hours or more after food
- 7.0 mmol/L within 2 hours of food
- Diagnosis of GDM is made on OGTT as follows:
- Fasting glucose > 5.5 mmol/L or
- 2 hour glucose > 9.0 mmol/L
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Management of GDM
- Refer to Combined Diabetes Antenatal team at Perth Royal Infirmary or Ninewells Hospital.
- Dietary advice should be given in all cases.
- If fasting or pre-prandial glucose is consistently greater than 6mmol/L, insulin should be introduced
(usually b.d. regimen will suffice)
- Glucose targets are similar to patients with established diabetes
- In most cases, insulin can be discontinued at delivery
- Ensure that normoglycaemia returns after delivery
- A 75g OGTT should be performed at around 6 weeks post-partum and the results interpreted according to WHO criteria
- The condition is associated with an increased risk of future diabetes (usually Type 2 DM)
Check fasting plasma glucose annually in women with a history of GDM to identify asymptomatic diabetes and screen for the
condition in a future pregnancy.
Women with previous GDM should be made aware of the benefits of exercise and importance of weight control, to avoid
the development diabetes.
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Contraception
Contraception should be discussed with all diabetes women in the child-bearing age group.
- Combined Oral Contraceptive Pill (OCP)
- Low dose oestrogen preparations are safe for use in the majority of diabetes women
- They may cause a rise in BP and raise HDL cholesterol and triglycerides (oestrogen).
- Monitor BP, weight and HbA1c twice yearly, assess lipids annually and discontinue if hypertension or deteriorating
lipid metabolism occurs.
- Avoid when complications of diabetes or risk factors for vascular disease present or in older
women (> 35 years). However a value judgement should be made in women for whom avoidance of pregnancy is essential.
- Progestogen-Only Pill (POP)
- Advantages are lack of vascular side-effects or effects on lipid metabolism.
- Omission is more likely to result in pregnancy than with the combined OCP.
- Irregular periods or inter-menstrual bleeding may occur
- Injectable and implantable progestogens are suitable for some patients, particularly if compliance is an issue.
However deterioration in glycaemic control may occur.
- Intra-Uterine Contraceptive Device
- The main advantage is the lack of metabolic effects
- There is a theoretical risk of infection causing salpingitis
- Mechanical Contraception
- Not recommended if it is essential to avoid pregnancy due to the high failure rate.
- Sterilisation
- Sterilisation may be advised if further pregnancy represents a serious risk to health.
- Obesity adds to the risk of the procedure and the failure rate is 0-0.5 per women years
Hormone Replacement Therapy in Diabetes
Diabetes is not a contraindication to the use of Hormone Replacement Therapy. Advice on use of HRT in any woman applies equally to women with diabetes.
RCPE Consensus Statement on Hormone Replacement Therapy October 2003
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