PRESENTER : DR NUR NA’IMAH (MD UKM)SUPERVISOR : DR NORHAYATI

GESTATIONAL DIABETES MELLITUS

1.INTRODUCTION2.DEFINITION3.PHYSIOLOGICAL CHANGES4.RISK FACTORS OF GDM 5.WHEN TO SCREEN6.HOW TO DIAGNOSE GDM7.EFFECTS OF

a.DM ON PREGNANCY TO BABY & MOTHER

b.PREGNANCY ON DM8.MANAGEMENT

INTRODUCTION OF GDM Prevalance of GDM in Malaysia : 12.7-24.9% from

1993-2003

Diabetes prevalence had increased from 8.3% (1996) to 14.9% (2006)

Diabetes admission based on type of diabetes (1994-2004): GDM represent ≈ 30% of total admission

Prevalence of GDM:

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Source: Chan et.al.1993; Shamsuddin et. Al. 2001 ; Idris et.al 2009

Source: NHMS III 2006

Source : Ministry of Health Malaysia 2007

Year Author Study Location Prevalence of GDM (%)

1993 Chan UMMC 12.72001 Shamsuddin et al. UKMMC 24.92009 Idris et al. Alor Setar 18.3

DEFINITION OF GDMGDM is defined as any degree of

glucose intolerance with onset or first recognition during pregnancy.

and disappear after 6 weeks post partum

After 6 weeks post partum , if MGTT NORMAL = GDM ABNORMAL = TYPE 2 DM

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Source: American Diabetes Association 2009

PHYSIOLOGICAL CHANGES

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During pregnancy, there is a state called DIABETOGENIC STATE, peak @ 28-32w

Due to ↑ hormone produced by placenta : HPL, CORTISOL (insulin antagonist) → relative insulin resistance

Glucose crosses the placenta by facilitated diffusion & fetal blood glucose level closely follow the maternal level

RISK FACTORS OF GDM

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Source : Malaysia CPG management of DM 4th edition , 2007• PCOS• Increase weight gain > 0.5 kg/ week• Recurrent vaginal candidiasis / other infections• USG : Macrosomic baby / abnormal fetus• Polyhydramnios • Previous congenital anomalies• Previous unexplained IUD• Previous stillbirth• Previous recurrent miscarriages

WHEN TO SCREEN?

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When pt is having the risk factors no matter what is the POA

For example : Pt is < 10 weeks POA with risk factors → MGTT If NORMAL → repeat at 28w and if still NORMAL →

repeat at 32w If ABNORMAL → BSP

Screen high-risk populationgroups during the first trimester of pregnancy in order to detect

previously undiagnoseddiabetes mellitus.

Source : WHO

+high risk pt (Previous GDM, family history, and glycosuria ≥1+ in 2 occasions / ≥ 2+ in 1 occasions) should be tested on 16-18w → repeat at 24 -28w if normal

MGTT should not be done < 16 weeks because mother is subjected to hyperemesis.

Source: NICE guideline 2008-DM in Pregnancy

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HOW TO DIAGNOSE GDM?

Source : Malaysia CPG management of DM 4th edition , 2007

If pt is having risk factors of GDM – she need to be screening by doing MGTT

If MGTT abnormal → BSP • To decide management : diet control or insulin• To monitor glucose control

Normal : 5/6/6/7 or 4-6 mmol/l Abnormal : 2 or more readings → insulin

Fasting 6.1 mmol/l (ADA uses 5.6mmol/l)

2 hours 7.8 mmol/l (just remember 5,6,7,8)

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ADA/WHO ACOG NICEHigh risk women

should be screened as soon

as feasible

screen allpregnant women

(universalscreening)

16–18weeks if prior

GDM; 24–28

weeks if risk factors

If normal, to repeat at 24 – 28 weeks100 g glucose 100 g glucose 75 g glucose(2 or more elevated) (2 or more elevated) 1 or more elevatedFasting 5.3 mmol/l1-h 10.0 mmol/l2-h, 8.6 mmol/l (only 2 h if 75-gglucose used)3-h, 7.8 mmol/l

Fasting 5.3 mmol/l1-h 10.0 mmol/l2-h, 8.6 mmol/l (only 2 h if 75-gglucose used)3-h, 7.8 mmol/l

Fasting 7.0 mmol/l2-h 7.8 mmol/l

Frequency of MonitoringFrequency should be individualized Ideal to have self blood glucose

monitoring(SBGM)

satisfactory BSP → on diet control: do BSP monitoring 4 weekly until 36 weeks

Poor BSP → on insulin therapy: do BSP monitoring 2 weekly 10

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RULE OF THUMB of Insulin commencement in GDM – MUST BE combination of short acting insulin (actrapid) + intermediate acting insulin (insulatard).

• Insulatard is normally BD dosage, but is used as OD dose in GDM

• The dosage of insulin is based on the BSP result. The higher the BSP derangement, the higher the dose of insulin to be started.

• Normally, patient will be started on 8/8/8/8 (actrapid/ actrapid/ actrapid/ insulatard).

SEQUENCE OF MANAGEMENT : - Diet control-> BSP deranged -> insulin ->

HBGM level still high -> insulin dose increment-> glucose level still high-> insulin+metformin

EFFECTS OF DM TO PREGNANCY

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PERIOD EFFECTS

1. PRE PREGNANCY Infertility2. ANTEPARTUM

1ST TRIMESTER(uncontrolled DM)

1. Miscarriage2. Fetal anomalies

2ND TRIMESTER 1. Recurrent UTI 2. Vaginal candidiasis3. Pre eclampsia4. Polyhydramnios

3RD TRIMESTER 1. IUGR (long standing DM → vasculopathy)2. Macrosomic baby (5-15%)3. Unexplained IUD

3. INTRAPARTUM Shoulder dystocia1. Birth asphyxia2. Risk of used of instrumental delivery3. Risk of operative delivery

4. POSTPARTUM 1. PPH, extended tear2. Hypoglycaemia (common, 50%) ,RDS ,

NNJ, polycythaemia, prematurity

Source : Obstetrics Normal and Problem Pregnancies 3rd edition. 1996

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EFFECTSMOTHER

1. Recurrent infections 2. Pre eclampsia3. Risk of operative delivery – due to

unstable/ presentation4. Polyhydramnios5. Possible risk of TOP if diabetic

nephropathyBABY 1. Miscarriage – d/t abnormal fetus →

chromosomal anomalies2. Congenital anomalies

• CVS : VSD, ASD, transposition of great artery

• CNS : neural tube defects• RENAL : agenesis• Sacral agenesis , caudal regression

syndrome3. Unexplained IUD4. Macrosomic baby5. Prematurity

EFFECTS OF PREGNANCY TO DM

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• a/w hyperemesis, infection, • d/t uncontrolled lipolysis & a

restrained ↑ gluconeogenesis d/t insulin deficiency

KETOACIDOSIS

• 2x ↑ risk• d/t reversible change in

osmotic pressure RETINOPATHY

• Risk of PE & IUGRVASCULOPATHY

• ↑ cardiac load in pregnancy

CARDIOMYOPATHY

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MANAGEMENT OF GDM

Pre pregnancy

Antenatal

Intrapartum

Postpartum

Pre pregnancy

1. Education : Counseling is important2. Achieve good glycaemic control :

before conception, aim for HbA1c <6.5%

3. Assessment of severity : DM complication

4. General health : stop smoking, optimize BW

5. Folic acid : 5mg OD 12w before conception

6. Contraception : until good control. Pregnancy should be planned

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MEASURES SIGNIFICANCEJoint clinic (obstetrician and physician)

Better control of pre morbidities

Good glycaemic control preconception and throughout pregnancy

-reduces risk of complications-Assessed by Hba1c level( Hba1c < 6.1% reduces risk of congenital malformation)

Avoid unplanned pregnancies

-risks associated with pregnancies complicated by diabetes increase with the duration of diabetes

-glycaemic targets, monitoring, medications for diabetes and medications for complications of diabetes will need to be reviewed before and during pregnancy

17Source: NICE guideline 2008-DM in Pregnancy

MEASURES SIGNIFICANCE

Role of diet, exercise, body weight

-To refer dietician-reduce weight if preconception BMI > 27kg/m2 -medical nutrition therapy-T.folate 5mg OD for 1st trimester

Assessment for diabetic nephropathy

-Serum creatinine > 120 umol/l-Total protein excretion > 2g/ day-Estimated GFR < 45 ml/min*to refer nephrologist **if already pregnant, eGFR is not used

- Thrombophylaxis needed if excretion > 5g/day

18Source: NICE guideline 2008-DM in Pregnancy

MEASURES SIGNIFICANCEAssessment for diabetic retinopathy- Preconception and during pregnancy

-Retinopathy tends to get worsen during pregnancy

-assessment by digital imaging with mydriasis following first antenatal clinic appointment and again at 28 weeks if the first assessment is normal.

-If any diabetic retinopathy is present, an additional retinal assessment should be performed at 16–20 weeks.

-pre proliferative diabetic retinopathy diagnosed during pregnancy should have ophthalmological follow-up for at least 6 months following the birth

-should not be considered a contraindication to vaginal birth. 19Source: NICE guideline 2008-DM in Pregnancy

ANTENATAL CARE Aim of treatment : to achieve the best possible control

of blood-glucose concentrations without the risk of the hypoglycaemia

Optimise blood sugar level Diet control and lifestyle modification If conservative mx fails to maintain satisfactory → BSP after 1-2

weeks Insulin therapy is indicated when diet fails Obstetric management

Serial growth scan detect fetal macrosomia / IUGR Doppler ultrasound & CTG fetal well being

Monitor BP *Detail scan : (20-24w) screening for risk stratification

of aneuploidy 20

Timing of Delivery

Diet control EDD Insulin therapy → 38 wIf complications anticipated---ELLSCS

Why not > 38w? fluctuation of glucose → met. acidosis →sudden IUD the decline function of the placenta that normally start at

38 weeks.Why not < 38w?

The best balance for lung maturity d/t ↑ incidence of RDS - mat. hyperinsulinaemia interfere with substrate availibilty for surfactant production 21

INTRAPARTUM MANAGEMENTGENERAL :1. Inform obstetric specialist.2. SLIDING SCALE to be followed.3. Continuous partogram and CTG

monitoring.4. Appropriate analgesia.5. Anticipate complications eg.

Shoulder dystocia, PPH and fetal distress.

6. Maintain glucose levels at 4-6 mmol/L

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Investigations 4 Houly urine ketoneHourly dxt

In HUKM , if the reading of glucose is ≤ 7mmol/L, Dr normally check dextrostix 4 hourly instead of 1 hourly.

baseline BUSE and then 4 Hly

NBM , Maintain 1 pint D5% + 1 g KCl (100 mls/H)

Insulin infusion sliding scale GIK regime is the main regime used in patient with Diabetes in

pregnancy which is in labour. Sliding scale regime is just a subset within GIK regime for the insulin control/ I part only of the GIK regime.

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SLIDING SCALEDextrostix Insulin infusion

< 4 mmol/L(hypoglycemia)

Inform registrar stat(IV bolus 10ml D50% if <2mmol/L )

4-6.9 mmol/L Omit insulin

7-9.9 mmol/L 1 unit/hr

10-12mmol/L 2 unit/hr

> 12mmol/L Inform registrar

POST PARTUM

Stop insulin after delivery of placentaInsulin requirement drops immediately

after delivery by 60 -75%Dxt monitoring before t/o from LRReturn dose :

If GDM off insulin therapy and then monitor dxt regularly

If pre existing diabetes to continue pre-pregnancy insulin/OHA

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Breastfeeding : to prevent neonatal hypoglycemia ↔ fetal islet hyperplasia is common

CONTRACEPTION : ideally, non hormonal

→ IUCD / barrier methodRepeat MGTT 6/ 52 post partum

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SOURCE :1. Hanretty’s Obstetrics Illustrated2. Ten Teachers’s Obstetrics3. UKM’s Handbook of Labour Room Practise