Gestational diabetes is
commonly defined as
first recognized during
Glucose metabolism &
Due to placental production of anti-insulin
hormones, there is a state of insulin
hPL , cotisol ,prolactin, GH ,estrogen and
Compare to non pregnant women
Low FBS with high PPBS
Low renal threshold for glucose & ↑ GFR leads to
Increased production of insulin and high fasting
insulin may lead to functional failure of the
2. Previous history of GDM
3. Family history of diabetes
4. Racial origin
Asian and African-Caribbean
5. Maternal age more than 25
6. Previous macrosomic baby
7. Polycystic ovary syndrome
8. Multiple pregnancy
Screening & Diagnoses
75 g OGTT new diagnostics values
NICE/WHO IADPSG RECOMMENDED
mmol/l mg/l mmol/l mg/l mmol/l mg/l
FBS ≥7.0 126 ≥5.1 91.8 ≥5.1 91.8
1Hr ≥10.0 180 ≥10.0 180
2Hr ≥7.8 140.4 ≥8.5 153 ≥8.5 153
Low risk group at 24 – 28 week
High risk group at booking if normal again 24 – 28 week
One abnormal value enough for diagnosis
Recurrence risk of GDM is
30-60% lifetime risk in
developing , IGT or type 2
The accepted pathological mechanism by which GDM leads to
complications is known as the Pedersen hypothesis
shoulder dystocia, birth trauma
and related complications
Polyhydramnios and PPROM or PROM
Ca2+, Mg2+, Polycythemia & Jaundice
Rationale of treatment
o Its' treatment is also controversial.
o No clear guidelines and universally
accepted treatment plans available.
o However randomized trials show
o in treating the GDM
o The Australian Carbohydrate Intolerance Study
(ACHOIS) was published in 2005
o National Institute of Child Health and Human
development (NICHD) trial – USA 2009
Multi disciplinary approach
Close monitoring & treatment of
GDM are very important for
mother & baby
FBS 1hr PPBS 2hr PPBS
mmol/l mg/l mmol/l mg/l mmol/l mg/l
NICE UK 3.5-5.9 63-106 7.8 140
ACOG 5.3 95 7.2 130 6.7 120
5.3 95 7.8 140 6.7 120
You may have to test four times a day:
2. 1 or 2 hours after breakfast
3. 1 or 2 hours after lunch
4. 1 or 2 hours after dinner
Dietary pattern & calorie distributions
Bed time snack- 30%
Carbohydrate - 40-50% complex, high fiber;
Protein - 20%;
Fat - 30-40%(<10%saturated)
A healthy diet is one that includes a balance of foods from all the food groups, giving the nutrients,
vitamins, and minerals necessary for a healthy pregnancy
Women with gestational diabetes
often need regular, moderate
physical activity to help control
their blood sugar levels by
allowing insulin to work better.
Prenatal aerobics classes
However, a consultation and
approval by a health care provider
is needed before beginning any
physical activity during
• When diet and lifestyle modifications fail to control blood glucose within 1 to 2 weeks then
pharmacological treatment should be commenced.
RCT found basal bolus regime gives better control
compared to twice daily regime.
Metfor. Vs Insulin in GDM)
& Glibenclamide (both
drugs safe in pregnancy,
both cross the
placenta but no short term
and intermediate fetal
30-45% of patients in OHA
need supplementary insulin
to control their blood sugar.
Review every 1-2 weeks, more frequently if
Anomaly scan at 18-20 weeks
Serial ultrasound from 28 weeks to detect
Monitoring of glucose every 1-2 week
Frequency & timing of antenatal fetal
monitoring is controversial . Complicated
GDM needs early antenatal fetal monitoring
as early as 32 wks.
Can give antenatal steroids for fetal lung
maturation and may need additional insulin
Timing of delivery is controversial and if
uncomplicated can go up to 40wks.
However, decision should be made
according to the available informations.
Mode of delivery will depend on the
clinical as well as ultrasonographic
Diabetes should not be a
contraindication for VBAC
Intra natal care
GDM requiring pharmacological
therapy are best managed
intravenous insulin drips and
glucose monitoring hourly .
Others need only blood glucose
monitoring during labour.
Target blood sugar range 4-7mmol
per l(72-126mg per l)
Continuous fetal heart monitoring
is advisable during labour.
Exclude persisting hyperglycaemia before
discharge ( FBS or PPBS)
Breast feeding should be encouraged & neonate
blood sugar to be check 2–4 hours after birth.
Lifestyle advice (including weight control, diet
OGTT at the 6 week.
Every three year thereafter.
Early screening for diabetes in future
Contraception & preconception care.