Gestational Diabetes Yannis Dimitropoulos ST3 in Diabetes and Endocrinology Torbay Hospital Buckfast Abbey Diabetes and Endocrinology Training Day 07/05/2010
What we will Cover Definition and Aetiology of Gestational Diabetes Importance of diagnosis and treatment of Diabetes in pregnancy
Aims and modalities of treatment according to best available evidence
GESTATIONAL DIABETES(GDM) A carbohydrate intolerance of variable severity with its onset/first recognition in pregnancy
This includes GDM that reverts to normal carbohydrate tolerance post-partum, but also all undiagnosed DM1, DM2 and rare monogenic Diabetes first detected during pregnancy
Why does Gestational Diabetes Mellitus happen? Increasing prevalence of obesity in the population of women of childbearing age augments insulin resistance. Increasing maternal age also portends increased insulin resistance
Insulin resistance increases further during pregnancy
Deterioration of β cell function and insulin resistance in Type 2 diabetes 0 20 40 60 80 100 Age ß-cell function (%) – 10 –8 –6 –4 –2 0 2 4 6 – 12 30 40 50 60 70
Deterioration of β cell function and insulin resistance in Gestational DM 0 20 40 60 80 100 Age ß-cell function (%) – 10 –8 –6 –4 –2 0 2 4 6 – 12 30 40 50 60 70
Why is it important to treat Gestational Diabetes?
Pedersen Hypothesis (1954) Maternal hyperglycaemia leads to foetal hyperglycaemia which evokes an exaggerated response to Insulin which causes increased neonatal fat deposition and abdominal girth with increased birth weight.
The above was further supported by recent studies (HAPO study associations with neonatal anthropometrics, 2009)
Australian Carbohydrate Intolerance Study in Pregnant Women (ACHOIS) 2005 Randomized double-blind intervention trial: 1000 women with GDM randomly assigned to ‘Intensive’ versus ‘Routine’ care Diet and monitoring (2 weeks) Treat with insulin if 2 X FPG >5.5 and/or 2 X 2-hr post-prandial glucoses >7 (>8 if after 35/40) All treated with multiple Insulin injections
Significant reduction in the rate of perinatal complications in the intervention group (1%) compared to the routine care group (4%).
ACHOIS Results Outcome Intervention Routine Group Infants Number Number Total number 506 524 Birth weight 3335g 3482g Macrosomia (>4kg) 49 (10%) 110 (21%) Death (Neonatal/Stillbirth) 0 5 Stillbirth 0 3 Shoulder dystocia 7 16 Bone fracture 0 1 Nerve palsy 0 3 Jaundice 44 48
Hyperglycaemia and Adverse Pregnancy Outcomes (HAPO) 2008 Observational multi -centre study (25.505 patients with GDM) showing continuous graded associations of maternal blood glucose levels below those diagnostic of Diabetes with: -increased birth weight (strong association) -increased cord-blood serum C-peptide levels (strong association) -C-section (weaker association) -Neonatal hypoglycaemia (weaker association) -Premature (<37/40) delivery, -Shoulder dystocia/birth trauma,
-Preeclampsia and Hyperbilirubinaemia
Hyperglycaemia and Adverse Pregnancy Outcomes (HAPO) 2008 There were no obvious glucose thresholds at which risks increased.
The results were applicable to all centres and were independent of other risk factors.
International Association of Diabetes and Pregnancy Study Groups (IADPSG) Consensus panel (2008) The panel recommends testing of FBG, HbA1c or RPG on all high-risk pregnant women. Diagnostic of overt Diabetes: FPG ≥ 7.0, HbA1c ≥ 6.5%, RPG ≥ 11.1 (Treat as established pregnant diabetic) Diagnostic of GDM: FPG ≥ 5.1 but <7.1 If results not diagnostic of Diabetes (FPG < 5.1) then 75g OGTT at weeks 24-28 for all pregnant women at risk
Overt Diabetes if FPG ≥ 7.0
NICE Guidelines 2008
CEMACH: adverse outcomes in pregnant women with type 1 and type 2 diabetes, 2002/3 and 2007
NICE -Risks of Gestational Diabetes in Pregnancy Birth trauma (to mother and baby) Transient neonatal morbidity Obesity and/or Diabetes developing later on in baby’s life
increased risk of the mother developing GDM with following pregnancies and Diabetes later in life
NICE -Risk Factors for Screening for GDM Previous macrosomic baby 4.5kg or above Foetal abdominal circumference >97 th centile on USS Previous Gestational Diabetes Family history of Diabetes (first degree) Family origin with a high prevalence of Diabetes
(South Asian, Afro-Caribbean, Middle Eastern, Chinese)
The Torbay Hospital Antenatal Diabetes Clinic referral process If previously diagnosed with GDM, Obstetric Clinic review with dating scan (12/40) for OGTT at earliest opportunity or proceed directly to CBS monitoring if previous Insulin-treated GDM. For all others with risk factors OGTT at 28/40 Refer to Diabetes ANC if: Fasting blood glucose >5.5 mmol/l Low-risk GDM if 2hr glucose 7.8-8.5 mmol/l
High-risk GDM if 2hr glucose >8.5 mmol/l
Low vs. High Risk GDM management If macrosomia or polyhydramnios on USS, refer to Diabetes ANC directly.
If USS normal, review by midwife for diet and lifestyle advice. CBS monitoring for 1 week and review by Diabetes Specialist Midwife. If CBS <5.5 fasting and <7.0 post-prandial, for repeat 1 week CBS monitoring at 33/40 and repeat growth scan at 36/40.
The Torbay Hospital Diabetes Antenatal Clinic Diabetes in Pregnancy Specialist Nurse Specialist Diabetes Dietician Consultant Diabetologist (and/or SpR)
Diabetes Specialist Midwife
The Torbay Hospital Diabetes Antenatal Clinic CBS values and patterns are reviewed in association with dietary, especially carbohydrate intake. Further patient education regarding the significance of monitoring blood sugars in pregnancy and the effect of dietary intake on CBS readings. In some cases, a further week of monitoring with tight dietary control Progression to Insulin treatment if CBS still high. Patients may need a full basal Bolus type regime with TDS short-acting Novorapid and Insulatard nocte ab initio or insulin at certain times of the day to begin with. Insulin requirements gradually increase up to week 37/40, then decline. For selected cases, Metformin or Glibenclamide are used. The aims of the treatment are: fasting values <5.5mmol/l
post-meal values <7.0mmol/l
The Torbay Hospital Diabetes Antenatal Clinic Intra-partum management plan is outlined in the multi-disciplinary “Diabetes in Pregnancy” notes by week 32/40. For all DM1, DM2 and GDM patients on Insulin, Sliding-scale Insulin is usually started whilst in established labour and stopped post-vaginal delivery. Sliding-scale Insulin may be continued for a short period of time in cases of C-Section.
Advice regarding GDM risk in future pregnancies, the importance of weight-control and screening prior to future planned pregnancies. Post-partum 6/52 FPG
REFERENCES ACHOIS Trial NEJM June 2005 Vol. 352 no 24, pp. 2477-2486 HAPO Study NEJM May 2008 Vol. 358, no 19, pp. 1991-2003 HAPO study associations with neonatal anthropometrics 2009 CEMACH: adverse outcomes in pregnant women with type 1 and type 2 diabetes, 2002/3 and 2007 IADPSG Consensus Panel statement 2008 NICE guideline: Diabetes in Pregnancy March 2008 South Devon Healthcare NHS Foundation Trust clinical guideline 0485: Diabetes in Pregnancy (reviewed 2009) Effects of treatment in women with GDM: systematic review and meta-analysis BMJ April 2010 vol. 340: p. 796
Medical Management of Diabetes in Pregnancy. Rob Dyer, Kath Williams, Jane Hogg and Sarah Thorne Torbay 2010