This document discusses gestational diabetes mellitus (GDM), including its definition, incidence rates, pathophysiology, diagnostic criteria, risks, management, and postnatal care. GDM is glucose intolerance that begins during pregnancy. It affects 3-15% of pregnancies and increases risks for both mother and baby. Babies are at higher risk of macrosomia, injury during birth, and hypoglycemia. Mothers face increased risks of preeclampsia, cesarean delivery, and developing diabetes after pregnancy. Treatment involves diet, exercise, blood glucose monitoring, and possibly antidiabetic medications. After delivery, women with a history of GDM require screening and lifestyle changes to prevent subsequent diabetes.

1. Dr .YASMIN AKTAR
MD Phase-B Resident
Department of Endocrinology
BSMMU

2. Gestational diabetes mellitus
(GDM)
It is defined as any degree of glucose
intolerance with onset or first recognition
during pregnancy, whether or not the
condition persisted after pregnancy, and
not excluding the possibility that
unrecognized glucose intolerance may
have antedated or begun concomitantly
with the pregnancy

3. Incidence
 3 to 15% of all pregnancies are
complicated by diabetes
 0.2% to 0.5% of all pregnancies occur in
women with pre-existing diagnosis of
type 1 DM
 similar number has pre-existing type 2
DM

4. Pathophygiology
 Insulin resistance
Production of placental Somatomamotropin
Increased production of cortisol, estriol,
progesterone
Increased insulin destruction by kidney &
placenta

5.  Increased lipolysis
Mother uses fat for her caloric needs
& serves glucose for fetal needs
 Changes of gluconeogenesis
Fetus preferentially utilizes alanine
& other amino acids deprivng the mother
of major neoglucogenic source

6. White classification
 Based on maternal and obstetric risk
factors, graded from A (best) to F (worst)
designed to predict pregnancy outcomes

8.  1971 and further updated in 1980 to
incorporate ischemic heart disease and
renal transplantation

9. Criteria for GDM(ADA)
Test 75 gm OGTT Measurement
Plasma glucose
 Fasting ≥ 5.1mmol/L
 1h ≥ 10.0 mmol/L
 2h ≥ 8.5 mmol/L

10. WHO recommended 75gm
OGTT criteria for GDM
Time point of OGTT Glucose values (mmol/L)
0 hour ≥ 6.1
02 hour ≥7.8
(Satisfying both or any of these
values)

11. GDM risk assessment:
ascertain at 1st ANC
Low risk
Age < 25 yrs
No known DM in 1st degree relative
Weight normal before pregnancy
Weight normal at birth
No hx. Of abnormal glucose metabolism
No history of poor obstetrics outcome

12. Average risk :
 Perform blood glucose testing at 24-28
wks using:
 One-step procedure: Diagnostic OGTT
on all subjects

13. High-risk:
 Perform blood glucose testing as soon
as feasible :
Maternal age >35 yrs
BMI >30kg/m2
Strong FH. of type II DM
Previous Hx. Of : GDM, impaired
glucose metabolism, or glucosuria

14.  If GDM is not Dx. repeated at 24-28 wks or
at any time a pt. has a symtoms or signs
suggestive of hyperglycemia

15. Adverse outcome

16. Newborn baby

17. Related to fetus
 Macrosomia (> 4kg, 20–30% of infants
whose mothers have GDM)
FBS > 105 mg/ dl
Maternal hyperglycemia
Fetal hyperglycemia
Fetal hyperinsulinemia
Excessive Fetal growth & adiposity

18. Macrosomic baby Normal baby

19. Related to fetus cont………
 Shoulder dystocia or birth injury
 Stillbirth
 Perinatal mortality
 Congenital malformation ( women with
fasting hyperglycemia )
 Polycythemia (Hyperglycemia is a
stimulus for erythropoietin production)

20. Related to neonate
 Hypoglycemia(maternal hyperglycemia
causing fetal hyperinsulinemia)-<1.7mmol/l
 Hyperbilirubinemia- ≥20mg/dl
 Hypocalcemia
 Intensive neonatal care
 RDS
 Neonatal death

21.  Long-term complications
Increased risk of glucose intolerance
Diabetes
Obesity

22. Related to mother
 Preeclampsia(≥140mmhg SBP or ≥90
DBP + proteinuria- + or more or UTP-
≥300mg/dl)
 Hypertension(related to insulin resistance)
 Premature delivery
 Ketoacidosis
 Urinary and genital tract infections

23.  Polyhydramnios
 Increased risk of
cesarean delivery
 Increased risk of
developing
diabetes after
pregnancy

24. Management of gestational
diabetes
 Initial management is with diet and
exercise
 women with GDM need to be taught to
SMBG and perform daily tests fasting and
1 - hour after meals
 If glycemic targets are not met within 2
weeks antidiabetic therapy is required

25. Maternal assessment
 BP
 Wt
 A/E-for hydromnios, fetal growth
 Urine for glucose,protein & pus cell

26. Fetal assessment
 USG
macrosomia
polyhydromnios
 Fetal monitoring
Fetal kick count
NST
BPL

27. Time of delivery
 Duration of pregnancy
 Control of diabetes
 Presence of complications-
PIH,macrosomia
 Past obstetrics history
 Tests o fetal well being

28. Mode of delivery
 Parity
 Bishop’s score of cervix
 Adequacy of pelvis
 Estimated fetal wt or macrosomia
 Associated maternal & fetal complication

29. Postnatal management
 Breastfeeding
Prevent hypoglycemia
Reduce insulin requrement by 25%
 Diabetes following GDM screening &
Prevention

30. Women with GDM are at increased risk
of developing diabetes
 Risk factors:
• Family origin with high prevalence of
diabetes (e.g. South Asian, Afro-
Caribbean, Middle Eastern)
• Treatment with insulin in pregnancy;
• Maternal obesity
• Weight gain postpartum &
• Family h/o diabetes

31. Acknowledgement